백준 #9251 LCS [Python]

x= input()
y= input()

dp = [[0] * (len(y)+1) for _ in range(len(x)+1)]

for i in range(1, len(x)+1):
    for j in range(1, len(y)+1):
        if x[i-1]==y[j-1]:
            dp[i][j] = dp[i-1][j-1] +1
        else:
            dp[i][j] = max(dp[i][j-1], dp[i-1][j])

print(dp[len(x)][len(y)])