19 lines
400 B
Python
19 lines
400 B
Python
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#!/usr/bin/env python3
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from math import factorial
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def bin(n, k):
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if k > n:
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return 0
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return factorial(n) // (factorial(n-k)*factorial(k))
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def strings(k):
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k -= 2
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s = 0
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for inter in range(25):
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for i in range(0,k+1):
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s += (25-inter) * 2**i * bin(inter, i) * bin(24-inter, k-i)
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return s
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print(max((2**k - k - 1) * bin(26, k) for k in range(2, 27)))
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