706 lines
22 KiB
Markdown
706 lines
22 KiB
Markdown
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# 30 seconds of code [](https://gitter.im/30-seconds-of-code/Lobby)
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> Curated collection of useful Javascript snippets that you can understand in 30 seconds or less.
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- Use <kbd>Ctrl</kbd> + <kbd>F</kbd> or <kbd>command</kbd> + <kbd>F</kbd> to search for a snippet.
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- Contributions welcome, please read the [contribution guide](CONTRIBUTING.md).
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- Snippets are written in ES6, use the [Babel transpiler](https://babeljs.io/) to ensure backwards-compatibility.
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## Contents
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* [Anagrams of string (with duplicates)](#anagrams-of-string-with-duplicates)
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* [Average of array of numbers](#average-of-array-of-numbers)
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* [Bottom visible](#bottom-visible)
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* [Capitalize first letter of every word](#capitalize-first-letter-of-every-word)
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* [Capitalize first letter](#capitalize-first-letter)
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* [Chain asynchronous functions](#chain-asynchronous-functions)
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* [Check for palindrome](#check-for-palindrome)
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* [Chunk array](#chunk-array)
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* [Count occurrences of a value in array](#count-occurrences-of-a-value-in-array)
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* [Current URL](#current-url)
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* [Curry](#curry)
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* [Deep flatten array](#deep-flatten-array)
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* [Difference between arrays](#difference-between-arrays)
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* [Distance between two points](#distance-between-two-points)
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* [Divisible by number](#divisible-by-number)
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* [Escape regular expression](#escape-regular-expression)
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* [Even or odd number](#even-or-odd-number)
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* [Factorial](#factorial)
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* [Fibonacci array generator](#fibonacci-array-generator)
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* [Filter out non unique values in an array](#filter-out-non-unique-values-in-an-array)
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* [Flatten array](#flatten-array)
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* [Get max value from array](#get-max-value-from-array)
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* [Get min value from array](#get-min-value-from-array)
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* [Get native type of value](#get-native-type-of-value)
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* [Get scroll position](#get-scroll-position)
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* [Greatest common divisor (GCD)](#greatest-common-divisor-gcd)
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* [Hamming distance](#hamming-distance)
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* [Head of list](#head-of-list)
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* [Initial of list](#initial-of-list)
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* [Initialize array with range](#initialize-array-with-range)
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* [Initialize array with values](#initialize-array-with-values)
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* [Last of list](#last-of-list)
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* [Measure time taken by function](#measure-time-taken-by-function)
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* [Median of array of numbers](#median-of-array-of-numbers)
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* [Object from key value pairs](#object-from-key-value-pairs)
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* [Percentile](#percentile)
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* [Pipe](#pipe)
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* [Powerset](#powerset)
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* [Promisify](#promisify)
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* [Random integer in range](#random-integer-in-range)
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* [Random number in range](#random-number-in-range)
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* [Randomize order of array](#randomize-order-of-array)
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* [Redirect to url](#redirect-to-url)
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* [Reverse a string](#reverse-a-string)
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* [RGB to hexadecimal](#rgb-to-hexadecimal)
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* [Run promises in series](#run-promises-in-series)
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* [Scroll to top](#scroll-to-top)
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* [Shuffle array values](#shuffle-array-values)
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* [Similarity between arrays](#similarity-between-arrays)
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* [Sort characters in string (alphabetical)](#sort-characters-in-string-alphabetical)
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* [Sum of array of numbers](#sum-of-array-of-numbers)
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* [Swap values of two variables](#swap-values-of-two-variables)
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* [Tail of list](#tail-of-list)
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* [Truncate a string](#truncate-a-string)
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* [Unique values of array](#unique-values-of-array)
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* [URL parameters](#url-parameters)
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* [UUID generator](#uuid-generator)
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* [Validate number](#validate-number)
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* [Value or default](#value-or-default)
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### Anagrams of string (with duplicates)
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Use recursion.
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For each letter in the given string, create all the partial anagrams for the rest of its letters.
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Use `Array.map()` to combine the letter with each partial anagram, then `Array.reduce()` to combine all anagrams in one array.
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Base cases are for string `length` equal to `2` or `1`.
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```js
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const anagrams = str => {
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if(str.length <= 2) return str.length === 2 ? [str, str[1] + str[0]] : [str];
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return str.split('').reduce( (acc, letter, i) =>
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acc.concat(anagrams(str.slice(0, i) + str.slice(i + 1)).map( val => letter + val )), []);
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}
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// anagrams('abc') -> ['abc','acb','bac','bca','cab','cba']
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```
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### Average of array of numbers
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Use `Array.reduce()` to add each value to an accumulator, initialized with a value of `0`, divide by the `length` of the array.
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```js
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const average = arr =>
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arr.reduce( (acc , val) => acc + val, 0) / arr.length;
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// average([1,2,3]) -> 2
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```
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### Bottom visible
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Use `scrollY`, `scrollHeight` and `clientHeight` to determine if the bottom of the page is visible.
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```js
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const bottomVisible = _ =>
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document.documentElement.clientHeight + window.scrollY >= document.documentElement.scrollHeight || document.documentElement.clientHeight;
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// bottomVisible() -> true
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```
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### Capitalize first letter of every word
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Use `replace()` to match the first character of each word and `toUpperCase()` to capitalize it.
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```js
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const capitalizeEveryWord = str => str.replace(/\b[a-z]/g, char => char.toUpperCase());
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// capitalizeEveryWord('hello world!') -> 'Hello World!'
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```
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### Capitalize first letter
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Use `slice(0,1)` and `toUpperCase()` to capitalize first letter, `slice(1)` to get the rest of the string.
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Omit the `lowerRest` parameter to keep the rest of the string intact, or set it to `true` to convert to lower case.
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```js
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const capitalize = (str, lowerRest = false) =>
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str.slice(0, 1).toUpperCase() + (lowerRest? str.slice(1).toLowerCase() : str.slice(1));
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// capitalize('myName', true) -> 'Myname'
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```
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### Chain asynchronous functions
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Loop through an array of functions containing asynchronous events, calling `next` when each asynchronous event has completed.
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```js
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const chainAsync = fns => { let curr = 0; const next = () => fns[curr++](next); next(); }
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/*
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chainAsync([
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next => { console.log('0 seconds'); setTimeout(next, 1000); },
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next => { console.log('1 second'); setTimeout(next, 1000); },
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next => { console.log('2 seconds'); }
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])
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*/
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```
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### Check for palindrome
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Convert string `toLowerCase()` and use `replace()` to remove non-alphanumeric characters from it.
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Then, `split('')` into individual characters, `reverse()`, `join('')` and compare to the original, unreversed string, after converting it `tolowerCase()`.
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```js
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const palindrome = str =>
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str.toLowerCase().replace(/[\W_]/g,'').split('').reverse().join('') === str.toLowerCase().replace(/[\W_]/g,'');
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// palindrome('taco cat') -> true
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```
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### Chunk array
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Use `Array.apply()` to create a new array, that fits the number of chunks that will be produced.
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Use `Array.map()` to map each element of the new array to a chunk the length of `size`.
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If the original array can't be split evenly, the final chunk will contain the remaining elements.
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```js
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const chunk = (arr, size) =>
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Array.apply(null, {length: Math.ceil(arr.length/size)}).map((v, i) => arr.slice(i*size, i*size+size));
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// chunk([1,2,3,4,5], 2) -> [[1,2],[3,4],5]
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```
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### Count occurrences of a value in array
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Use `Array.reduce()` to increment a counter each time you encounter the specific value inside the array.
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```js
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const countOccurrences = (arr, value) => arr.reduce((a, v) => v === value ? a + 1 : a + 0, 0);
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// countOccurrences([1,1,2,1,2,3], 1) -> 3
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```
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### Current URL
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Use `window.location.href` to get current URL.
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```js
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const currentUrl = _ => window.location.href;
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// currentUrl() -> 'https://google.com'
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```
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### Curry
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Use recursion.
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If the number of provided arguments (`args`) is sufficient, call the passed function `f`.
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Otherwise return a curried function `f` that expects the rest of the arguments.
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If you want to curry a function that accepts a variable number of arguments (a variadic function, e.g. `Math.min()`), you can optionally pass the number of arguments to the second parameter `arity`.
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```js
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const curry = (f, arity = f.length, next) =>
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(next = prevArgs =>
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nextArg => {
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const args = [ ...prevArgs, nextArg ];
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return args.length >= arity ? f(...args) : next(args);
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}
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)([]);
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// curry(Math.pow)(2)(10) -> 1024
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// curry(Math.min, 3)(10)(50)(2) -> 2
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```
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### Deep flatten array
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Use recursion.
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Use `Array.reduce()` to get all elements that are not arrays, flatten each element that is an array.
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```js
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const deepFlatten = arr =>
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arr.reduce( (a, v) => a.concat( Array.isArray(v) ? deepFlatten(v) : v ), []);
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// deepFlatten([1,[2],[[3],4],5]) -> [1,2,3,4,5]
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```
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### Difference between arrays
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Use `filter()` to remove values that are part of `values`, determined using `includes()`.
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```js
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const difference = (arr, values) => arr.filter(v => !values.includes(v));
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// difference([1,2,3], [1,2]) -> [3]
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```
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### Distance between two points
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Use `Math.hypot()` to calculate the Euclidean distance between two points.
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```js
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const distance = (x0, y0, x1, y1) => Math.hypot(x1 - x0, y1 - y0);
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// distance(1,1, 2,3) -> 2.23606797749979
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```
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### Divisible by number
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Use the modulo operator (`%`) to check if the remainder is equal to `0`.
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```js
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const isDivisible = (dividend, divisor) => dividend % divisor === 0;
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// isDivisible(6,3) -> true
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```
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### Escape regular expression
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Use `replace()` to escape special characters.
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```js
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const escapeRegExp = str => str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
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// escapeRegExp('(test)') -> \\(test\\)
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```
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### Even or odd number
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Use `Math.abs()` to extend logic to negative numbers, check using the modulo (`%`) operator.
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Return `true` if the number is even, `false` if the number is odd.
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```js
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const isEven = num => Math.abs(num) % 2 === 0;
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// isEven(3) -> false
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```
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### Factorial
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Use recursion.
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If `n` is less than or equal to `1`, return `1`.
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Otherwise, return the product of `n` and the factorial of `n - 1`.
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```js
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const factorial = n => n <= 1 ? 1 : n * factorial(n - 1);
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// factorial(6) -> 720
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```
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### Fibonacci array generator
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Create an empty array of the specific length, initializing the first two values (`0` and `1`).
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Use `Array.reduce()` to add values into the array, using the sum of the last two values, except for the first two.
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```js
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const fibonacci = n =>
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Array(n).fill(0).reduce((acc, val, i) => acc.concat(i > 1 ? acc[i - 1] + acc[i - 2] : i),[]);
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// fibonacci(5) -> [0,1,1,2,3]
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```
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### Filter out non-unique values in an array
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Use `Array.filter()` for an array containing only the unique values.
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```js
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const unique = arr => arr.filter(i => arr.indexOf(i) === arr.lastIndexOf(i));
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// unique([1,2,2,3,4,4,5]) -> [1,3,5]
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```
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### Flatten array
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Use `Array.reduce()` to get all elements inside the array and `concat()` to flatten them.
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```js
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const flatten = arr => arr.reduce( (a, v) => a.concat(v), []);
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// flatten([1,[2],3,4]) -> [1,2,3,4]
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```
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### Get max value from array
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Use `Math.max()` combined with the spread operator (`...`) to get the maximum value in the array.
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```js
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const arrayMax = arr => Math.max(...arr);
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// arrayMax([10, 1, 5]) -> 10
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```
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### Get min value from array
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Use `Math.min()` combined with the spread operator (`...`) to get the minimum value in the array.
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```js
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const arrayMin = arr => Math.min(...arr);
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// arrayMin([10, 1, 5]) -> 1
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```
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### Get native type of value
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Returns lower-cased constructor name of value, "undefined" or "null" if value is undefined or null
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```js
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const getType = v =>
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v === undefined ? "undefined" : v === null ? "null" : v.constructor.name.toLowerCase();
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// getType(new Set([1,2,3])) -> "set"
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```
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### Get scroll position
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Use `pageXOffset` and `pageYOffset` if they are defined, otherwise `scrollLeft` and `scrollTop`.
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You can omit `el` to use a default value of `window`.
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```js
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const getScrollPos = (el = window) =>
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( {x: (el.pageXOffset !== undefined) ? el.pageXOffset : el.scrollLeft,
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y: (el.pageYOffset !== undefined) ? el.pageYOffset : el.scrollTop} );
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// getScrollPos() -> {x: 0, y: 200}
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```
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### Greatest common divisor (GCD)
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Use recursion.
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Base case is when `y` equals `0`. In this case, return `x`.
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Otherwise, return the GCD of `y` and the remainder of the division `x/y`.
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```js
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const gcd = (x , y) => !y ? x : gcd(y, x % y);
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// gcd (8, 36) -> 4
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```
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### Hamming distance
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Use XOR operator (`^`) to find the bit difference between the two numbers, convert to binary string using `toString(2)`.
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Count and return the number of `1`s in the string, using `match(/1/g)`.
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```js
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const hammingDistance = (num1, num2) =>
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((num1^num2).toString(2).match(/1/g) || '').length;
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// hammingDistance(2,3) -> 1
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```
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### Head of list
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Return `arr[0]`.
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```js
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const head = arr => arr[0];
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// head([1,2,3]) -> 1
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```
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### Initial of list
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Return `arr.slice(0,-1)`.
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```js
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const initial = arr => arr.slice(0,-1);
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// initial([1,2,3]) -> [1,2]
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```
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### Initialize array with range
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Use `Array(end-start)` to create an array of the desired length, `Array.map()` to fill with the desired values in a range.
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You can omit `start` to use a default value of `0`.
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```js
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const initializeArrayRange = (end, start = 0) =>
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Array.apply(null, Array(end-start)).map( (v,i) => i + start );
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// initializeArrayRange(5) -> [0,1,2,3,4]
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```
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### Initialize array with values
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Use `Array(n)` to create an array of the desired length, `fill(v)` to fill it with the desired values.
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You can omit `value` to use a default value of `0`.
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```js
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const initializeArray = (n, value = 0) => Array(n).fill(value);
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// initializeArray(5, 2) -> [2,2,2,2,2]
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```
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### Last of list
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Return `arr.slice(-1)[0]`.
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```js
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const last = arr => arr.slice(-1)[0];
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// last([1,2,3]) -> 3
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```
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### Measure time taken by function
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Use `performance.now()` to get start and end time for the function, `console.log()` the time taken.
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Pass a callback function as the argument.
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```js
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const timeTaken = callback => {
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const t0 = performance.now(), r = callback();
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console.log(performance.now() - t0);
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return r;
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}
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// timeTaken(() => Math.pow(2, 10)) -> 1024 (0.010000000009313226 logged in console)
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```
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### Median of array of numbers
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Find the middle of the array, use `Array.sort()` to sort the values.
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Return the number at the midpoint if `length` is odd, otherwise the average of the two middle numbers.
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```js
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const median = arr => {
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const mid = Math.floor(arr.length / 2), nums = arr.sort((a,b) => a - b);
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return arr.length % 2 !== 0 ? nums[mid] : (nums[mid - 1] + nums[mid]) / 2;
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}
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// median([5,6,50,1,-5]) -> 5
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// median([0,10,-2,7]) -> 3.5
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```
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### Object from key-value pairs
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Use `Array.reduce()` to create and combine key-value pairs.
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```js
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const objectFromPairs = arr => arr.reduce((a,v) => (a[v[0]] = v[1], a), {});
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// objectFromPairs([['a',1],['b',2]]) -> {a: 1, b: 2}
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```
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### Percentile
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Use `Array.reduce()` to calculate how many numbers are below the value and how many are the same value and
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apply the percentile formula.
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```js
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const percentile = (arr, val) =>
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100 * arr.reduce((acc,v) => acc + (v < val ? 1 : 0) + (v === val ? 0.5 : 0), 0) / arr.length;
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// percentile([1,2,3,4,5,6,7,8,9,10], 6) -> 55
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```
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### Pipe
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Use `Array.reduce()` to pass value through functions.
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```js
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const pipe = (...funcs) => arg => funcs.reduce((acc, func) => func(acc), arg);
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// pipe(btoa, x => x.toUpperCase())("Test") -> "VGVZDA=="
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```
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### Powerset
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Use `Array.reduce()` combined with `Array.map()` to iterate over elements and combine into an array containing all combinations.
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```js
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const powerset = arr =>
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arr.reduce( (a,v) => a.concat(a.map( r => [v].concat(r) )), [[]]);
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// powerset([1,2]) -> [[], [1], [2], [2,1]]
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```
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### Promisify
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Use currying to return a function returning a `Promise` that calls the original function.
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Use the `...rest` operator to pass in all the parameters.
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|
|
|
*In Node 8+, you can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original)*
|
|
|
|
```js
|
|
const promisify = func =>
|
|
(...args) =>
|
|
new Promise((resolve, reject) =>
|
|
func(...args, (err, result) =>
|
|
err ? reject(err) : resolve(result))
|
|
);
|
|
// const delay = promisify((d, cb) => setTimeout(cb, d))
|
|
// delay(2000).then(() => console.log('Hi!')) -> Promise resolves after 2s
|
|
```
|
|
|
|
### Random integer in range
|
|
|
|
Use `Math.random()` to generate a random number and map it to the desired range, using `Math.floor()` to make it an integer.
|
|
|
|
```js
|
|
const randomIntegerInRange = (min, max) => Math.floor(Math.random() * (max - min + 1)) + min;
|
|
// randomIntegerInRange(0, 5) -> 2
|
|
```
|
|
|
|
### Random number in range
|
|
|
|
Use `Math.random()` to generate a random value, map it to the desired range using multiplication.
|
|
|
|
```js
|
|
const randomInRange = (min, max) => Math.random() * (max - min) + min;
|
|
// randomInRange(2,10) -> 6.0211363285087005
|
|
```
|
|
|
|
### Randomize order of array
|
|
|
|
Use `Array.sort()` to reorder elements, utilizing `Math.random()` to randomize the sorting.
|
|
|
|
```js
|
|
const randomizeOrder = arr => arr.sort( (a,b) => Math.random() >= 0.5 ? -1 : 1);
|
|
// randomizeOrder([1,2,3]) -> [1,3,2]
|
|
```
|
|
|
|
### Redirect to URL
|
|
|
|
Use `window.location.href` or `window.location.replace()` to redirect to `url`.
|
|
Pass a second argument to simulate a link click (`true` - default) or an HTTP redirect (`false`).
|
|
|
|
```js
|
|
const redirect = (url, asLink = true) =>
|
|
asLink ? window.location.href = url : window.location.replace(url);
|
|
// redirect('https://google.com')
|
|
```
|
|
|
|
### Reverse a string
|
|
|
|
Use array destructuring and `Array.reverse()` to reverse the order of the characters in the string.
|
|
Combine characters to get a string using `join('')`.
|
|
|
|
```js
|
|
const reverseString = str => [...str].reverse().join('');
|
|
// reverseString('foobar') -> 'raboof'
|
|
```
|
|
|
|
### RGB to hexadecimal
|
|
|
|
Convert given RGB parameters to hexadecimal string using bitwise left-shift operator (`<<`) and `toString(16)`, then `padStart(6,'0')` to get a 6-digit hexadecimal value.
|
|
|
|
```js
|
|
const rgbToHex = (r, g, b) => ((r << 16) + (g << 8) + b).toString(16).padStart(6, '0');
|
|
// rgbToHex(255, 165, 1) -> 'ffa501'
|
|
```
|
|
|
|
### Run promises in series
|
|
|
|
Run an array of promises in series using `Array.reduce()` by creating a promise chain, where each promise returns the next promise when resolved.
|
|
|
|
```js
|
|
const series = ps => ps.reduce((p, next) => p.then(next), Promise.resolve());
|
|
// const delay = (d) => new Promise(r => setTimeout(r, d))
|
|
// series([() => delay(1000), () => delay(2000)]) -> executes each promise sequentially, taking a total of 3 seconds to complete
|
|
```
|
|
|
|
### Scroll to top
|
|
|
|
Get distance from top using `document.documentElement.scrollTop` or `document.body.scrollTop`.
|
|
Scroll by a fraction of the distance from top. Use `window.requestAnimationFrame()` to animate the scrolling.
|
|
|
|
```js
|
|
const scrollToTop = _ => {
|
|
const c = document.documentElement.scrollTop || document.body.scrollTop;
|
|
if(c > 0) {
|
|
window.requestAnimationFrame(scrollToTop);
|
|
window.scrollTo(0, c - c/8);
|
|
}
|
|
}
|
|
// scrollToTop()
|
|
```
|
|
|
|
### Shuffle array values
|
|
|
|
Create an array of random values by using `Array.map()` and `Math.random()`.
|
|
Use `Array.sort()` to sort the elements of the original array based on the random values.
|
|
|
|
```js
|
|
const shuffle = arr => {
|
|
let r = arr.map(Math.random);
|
|
return arr.sort((a,b) => r[a] - r[b]);
|
|
}
|
|
// shuffle([1,2,3]) -> [2, 1, 3]
|
|
```
|
|
|
|
### Similarity between arrays
|
|
|
|
Use `filter()` to remove values that are not part of `values`, determined using `includes()`.
|
|
|
|
```js
|
|
const similarity = (arr, values) => arr.filter(v => values.includes(v));
|
|
// similarity([1,2,3], [1,2,4]) -> [1,2]
|
|
```
|
|
|
|
### Sort characters in string (alphabetical)
|
|
|
|
Split the string using `split('')`, `Array.sort()` utilizing `localeCompare()`, recombine using `join('')`.
|
|
|
|
```js
|
|
const sortCharactersInString = str =>
|
|
str.split('').sort( (a,b) => a.localeCompare(b) ).join('');
|
|
// sortCharactersInString('cabbage') -> 'aabbceg'
|
|
```
|
|
|
|
### Sum of array of numbers
|
|
|
|
Use `Array.reduce()` to add each value to an accumulator, initialized with a value of `0`.
|
|
|
|
```js
|
|
const sum = arr => arr.reduce( (acc , val) => acc + val, 0);
|
|
// sum([1,2,3,4]) -> 10
|
|
```
|
|
|
|
### Swap values of two variables
|
|
|
|
Use array destructuring to swap values between two variables.
|
|
|
|
```js
|
|
[varA, varB] = [varB, varA];
|
|
// [x, y] = [y, x]
|
|
```
|
|
|
|
### Tail of list
|
|
|
|
Return `arr.slice(1)` if the array's `length` is more than `1`, otherwise return the whole array.
|
|
|
|
```js
|
|
const tail = arr => arr.length > 1 ? arr.slice(1) : arr;
|
|
// tail([1,2,3]) -> [2,3]
|
|
// tail([1]) -> [1]
|
|
```
|
|
|
|
### Truncate a String
|
|
|
|
Determine if the string's `length` is greater than `num`.
|
|
Return the string truncated to the desired length, with `...` appended to the end or the original string.
|
|
|
|
```
|
|
const truncate = (str, num) =>
|
|
str.length > num ? str.slice(0, num > 3 ? num-3 : num) + '...' : str;
|
|
// truncate('boomerang', 7) -> 'boom...'
|
|
```
|
|
|
|
### Unique values of array
|
|
|
|
Use ES6 `Set` and the `...rest` operator to discard all duplicated values.
|
|
|
|
```js
|
|
const unique = arr => [...new Set(arr)];
|
|
// unique([1,2,2,3,4,4,5]) -> [1,2,3,4,5]
|
|
```
|
|
|
|
### URL parameters
|
|
|
|
Use `match()` with an appropriate regular expression to get all key-value pairs, `Array.reduce()` to map and combine them into a single object.
|
|
Pass `location.search` as the argument to apply to the current `url`.
|
|
|
|
```js
|
|
const getUrlParameters = url =>
|
|
url.match(/([^?=&]+)(=([^&]*))?/g).reduce(
|
|
(a,v) => (a[v.slice(0,v.indexOf('='))] = v.slice(v.indexOf('=')), a), {}
|
|
);
|
|
// getUrlParameters('http://url.com/page?name=Adam&surname=Smith') -> {name: 'Adam', surname: 'Smith'}
|
|
```
|
|
|
|
### UUID generator
|
|
|
|
Use `crypto` API to generate a UUID, compliant with [RFC4122](https://www.ietf.org/rfc/rfc4122.txt) version 4.
|
|
|
|
```js
|
|
const uuid = _ =>
|
|
( [1e7]+-1e3+-4e3+-8e3+-1e11 ).replace( /[018]/g, c =>
|
|
(c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16)
|
|
);
|
|
// uuid() -> '7982fcfe-5721-4632-bede-6000885be57d'
|
|
```
|
|
|
|
### Validate number
|
|
|
|
Use `!isNaN` in combination with `parseFloat()` to check if the argument is a number.
|
|
Use `isFinite()` to check if the number is finite.
|
|
|
|
```js
|
|
const validateNumber = n => !isNaN(parseFloat(n)) && isFinite(n);
|
|
// validateNumber('10') -> true
|
|
```
|
|
|
|
### Value or default
|
|
|
|
Returns value, or default value if passed value is `falsy`.
|
|
|
|
```js
|
|
const valueOrDefault = (value, d) => value || d;
|
|
// valueOrDefault(NaN, 30) -> 30
|
|
```
|
|
|
|
## Credits
|
|
|
|
*Icons made by [Smashicons](https://www.flaticon.com/authors/smashicons) from [www.flaticon.com](https://www.flaticon.com/) is licensed by [CC 3.0 BY](http://creativecommons.org/licenses/by/3.0/).*
|
|
|