25 lines
564 B
Python
25 lines
564 B
Python
def kmp_algorithm(string):
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n = len(string)
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lps = [None] * n
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l, lps[0], i = 0, 0, 1 while i < n:
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if string[i] == string[l]:
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l += 1 lps[i] = l
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i += 1 else:
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if l != 0:
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l = lps[l-1]
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else:
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lps[i] = 0 i += 1 return lps
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def minadded(string):
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revstr = string[::-1]
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big_str = string + '$' + revstr
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lps = kmp_algorithm(big_str)
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return len(string) - lps[-1]
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s = input()
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nr = minadded(s)
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ans = s[-nr:] + s
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print(ans)
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