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Create longest common subsequence.py

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LCS Problem Statement: Given two sequences, find the length of longest subsequence present in both of them.
A subsequence is a sequence that appears in the same relative order, but not necessarily continious.
Example:"abc", "abg" are subsequences of "abcdefgh".
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dhruvsaini 2017-01-02 20:51:37 +05:30 committed by GitHub
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"""
LCS Problem Statement: Given two sequences, find the length of longest subsequence present in both of them.
A subsequence is a sequence that appears in the same relative order, but not necessarily continious.
Example:"abc", "abg" are subsequences of "abcdefgh".
"""
def LCS(s1, s2):
m = len(s1)
n = len(s2)
arr = [[0 for i in range(n+1)]for j in range(m+1)]
for i in range(1,m+1):
for j in range(1,n+1):
if s1[i-1] == s2[j-1]:
arr[i][j] = arr[i-1][j-1]+1
else:
arr[i][j] = max(arr[i-1][j], arr[i][j-1])
return arr[m][n]