32 lines
845 B
Python
32 lines
845 B
Python
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str1 = "AABA"
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str2 = "AZB"
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def lcs(text1, text2):
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n= len(text1)
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m= len(text2)
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# creates an [m+1][n+1] matrix, filled with zeros
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table=[[0]*(n+1) for _ in range(m+1)]
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for i in range(1, m+1):
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for j in range (1, n+1):
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# first char is the same, so add 1 to count
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if text2[i-1]==text1[j-1]:
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table[i][j]= 1+table[i-1][j-1]
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# first char is different, so break into subproblems and take the max
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else:
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table[i][j]=max(table[i-1][j],table[i][j-1])
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print( [0]*(n+1) )
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print( range(m+1) )
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print( table )
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print( max(table) ) # this get the last element at the end of the list
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return max(max(table)) # this gets the last element at the bottom right corner (last element of both lists)
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print( lcs(str1, str2))
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