34 lines
934 B
Python
34 lines
934 B
Python
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def rabin_karp_search(pat: str, txt: str) -> list:
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assert (len(pat) <= len(txt))
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d = 2560
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q = 101
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M = len(pat)
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N = len(txt)
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i = 0
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j = 0
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p = 0
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t = 0
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h = 1
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for i in range((M - 1)):
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h = ((h * d) % q)
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for i in range(M):
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p = (((d * p) + ord(pat[i])) % q)
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t = (((d * t) + ord(txt[i])) % q)
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found_at_index = []
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for i in range(((N - M) + 1)):
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if evaluate_condition(1, 'Eq', p, t):
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for j in range(M):
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if evaluate_condition(2, 'NotEq', txt[(i + j)], pat[j]):
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break
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j += 1
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if evaluate_condition(3, 'Eq', j, M):
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found_at_index.append(i)
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if evaluate_condition(4, 'Lt', i, (N - M)):
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t = (((d * (t - (ord(txt[i]) * h))) + ord(txt[(i + M)])) % q)
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if evaluate_condition(5, 'Lt', t, 0):
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t = (t + q)
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return found_at_index
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