26 lines
695 B
Markdown
26 lines
695 B
Markdown
---
|
|
title: linearSearch
|
|
tags: algorithm,array,beginner
|
|
---
|
|
|
|
Finds the first index of a given element in an array using the linear search algorithm.
|
|
|
|
- Use a `for...in` loop to iterate over the indexes of the given array.
|
|
- Check if the element in the corresponding index is equal to `item`.
|
|
- If the element is found, return the index, using the unary `+` operator to convert it from a string to a number.
|
|
- If the element is not found after iterating over the whole array, return `-1`.
|
|
|
|
```js
|
|
const linearSearch = (arr, item) => {
|
|
for (const i in arr) {
|
|
if (arr[i] === item) return +i;
|
|
}
|
|
return -1;
|
|
};
|
|
```
|
|
|
|
```js
|
|
linearSearch([2, 9, 9], 9); // 1
|
|
linearSearch([2, 9, 9], 7); // -1
|
|
```
|