131 lines
2.9 KiB
Markdown
131 lines
2.9 KiB
Markdown
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# 30-seconds-of-python-code
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Python implementation of 30-seconds-of-code.
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**Note**:- This is in no way affiliated with the original [30-seconds-of-code](https://github.com/Chalarangelo/30-seconds-of-code/).
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### chunk
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Chunks an array into smaller arrays of a specified size.
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Uses `range` to create a list of desired size. Then use `map` on this list and fill it with splices of `arr`
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```python
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from math import ceil
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def chunk(arr, size):
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return list(
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map(lambda x: arr[x * size:x * size + size],
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list(range(0, ceil(len(arr) / size)))))
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```
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``` python
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chunk([1,2,3,4,5],2) # [[1,2],[3,4],5]
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```
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### gcd
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Calculates the greatest common divisor between two or more numbers/lists.
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The `helperGcdfunction` uses recursion. Base case is when `y` equals `0`. In this case, return `x`. Otherwise, return the GCD of `y` and the remainder of the division `x/y`.
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Uses the reduce function from the inbuilt module `functools`. Also defines a method `spread` for javascript like spreading of lists.
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```python
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from functools import reduce
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def spread(arg):
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ret = []
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for i in arg:
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if isinstance(i, list):
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ret.extend(i)
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else:
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ret.append(i)
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return ret
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def gcd(*args):
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numbers = []
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numbers.extend(spread(list(args)))
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def _gcd(x, y):
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return x if not y else gcd(y, x % y)
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return reduce((lambda x, y: _gcd(x, y)), numbers)
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```
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``` python
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gcd(8,36) # 4
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```
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### lcm
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Returns the least common multiple of two or more numbers.
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Use the `greatest common divisor (GCD)` formula and the fact that `lcm(x,y) = x * y / gcd(x,y)` to determine the least common multiple. The GCD formula uses recursion.
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Uses `reduce` function from the inbuilt module `functools`. Also defines a method `spread` for javascript like spreading of lists.
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```python
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from functools import reduce
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def spread(arg):
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ret = []
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for i in arg:
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if isinstance(i, list):
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ret.extend(i)
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else:
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ret.append(i)
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return ret
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def lcm(*args):
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numbers = []
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numbers.extend(spread(list(args)))
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def _gcd(x, y):
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return x if not y else gcd(y, x % y)
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def _lcm(x, y):
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return x * y / _gcd(x, y)
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return reduce((lambda x, y: _lcm(x, y)), numbers)
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```
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``` python
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lcm(12, 7) # 84
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lcm([1, 3, 4], 5) # 60
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```
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### spread
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Implements javascript's spread syntax as a function. Flattens the list(non-deep) and returns an list.
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```python
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def spread(arg):
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ret = []
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for i in arg:
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if isinstance(i, list):
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ret.extend(i)
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else:
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ret.append(i)
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return ret
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```
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```python
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spread([1,2,3,[4,5,6],[7],8,9]) # [1,2,3,4,5,6,7,8,9]
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```
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## Credits
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*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/).*
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