24 lines
480 B
Python
24 lines
480 B
Python
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#!/usr/bin/env python3
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# Brute force
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from math import sqrt
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def main():
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low = 10*(int(sqrt(10203040506070809))//10)
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upp = int(sqrt(19293949596979899))
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for i in range(low+3, upp+1, 10):
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if is_num(i**2):
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return i*10
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for i in range(low+7, upp+1, 10):
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if is_num(i**2):
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return i*10
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return False
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def is_num(n):
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s = str(n)
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for i in range(9):
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if int(s[2*i]) != i+1: return False
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return True
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print(main())
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