43 lines
885 B
Markdown
43 lines
885 B
Markdown
### 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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``` |