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pattern_search.py
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pattern_search.py
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def KMPSearch(pat, txt):
M = len(pat)
N = len(txt)
lps = [0]*M
j = 0
computeLPSArray(pat, M, lps)
i = 0
while i < N:
if pat[j] == txt[i]:
i += 1
j += 1
if j == M:
print ("Found pattern at index " + str(i-j))
j = lps[j-1]
elif i < N and pat[j] != txt[i]:
if j != 0:
j = lps[j-1]
else:
i += 1
def computeLPSArray(pat, M, lps):
len = 0
lps[0]
i = 1
while i < M:
if pat[i]== pat[len]:
len += 1
lps[i] = len
i += 1
else:
if len != 0:
len = lps[len-1]
else:
lps[i] = 0
i += 1
txt = "ABABDABACDABABCABAB"
pat = "ABABCABAB"
KMPSearch(pat, txt)