23 lines
548 B
Python
23 lines
548 B
Python
## https://gist.github.com/sadikkuzu/af6a69d73f463b1b6b30aec15935dbc9
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# https://www.wikiwand.com/en/Happy_number
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# http://mathworld.wolfram.com/HappyNumber.html
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def square(x):
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return int(x) * int(x)
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def happy(number):
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return sum(map(square, list(str(number))))
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def is_happy(number):
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seen_numbers = set()
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while number > 1 and (number not in seen_numbers):
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seen_numbers.add(number)
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number = happy(number)
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return number == 1
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def is_happy2(n): # recursive
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return (n == 1 or n > 4 and is_happy2(happy(n))) |