Go: package main

import (
	. "fmt"
    "math"
)

// func init() { Println("----------------------------------------") }

func main() {
    const L_MAX = 1003

	var q int
	Scanf("%d", &q)
	X := make([]string, 0, 150)
	Y := make([]string, 0, 150)
	for i := 0; i < 2 * q; i++ {
	    var tmp string
	    Scanf("%s", &tmp)

	    if i % 2 == 0 {
	        X = append(X, tmp)
	    } else {
	        Y = append(Y, tmp)
	    }
	}

    for i := 0; i < q; i++ {
        dp := make([][]int, L_MAX)
        for k, _ := range dp {
            dp[k] = make([]int, L_MAX)
        }

        x, y := X[i], Y[i]

        // init
        isXFound := false
        for c := 0; c < len(x); c++ {
            if isXFound || y[0] == x[c] {
                dp[0][c] = 1
                isXFound = true
            }
        }
        isYFound := false
        for r := 0; r < len(y); r++ {
            if isYFound || x[0] == y[r] {
                dp[r][0] = 1
                isYFound = true
            }
        }

        for r := 1; r < len(y); r++ {
            for c := 1; c < len(x); c++ {
                // dp[r][c]
                if x[c] == y[r] {
                    dp[r][c] = int(math.Max(float64(dp[r - 1][c - 1] + 1), float64(dp[r][c])))
                }

                dp[r][c] = int(math.Max(float64(dp[r][c]), math.Max(float64(dp[r - 1][c]), float64(dp[r][c - 1]))))
            }
        }
        Println(dp[len(y) - 1][len(x) - 1])

        // LCSも求めておく
        // ans := ""
        // r, c := len(y) - 1, len(x) - 1
        // for r >= 0 && c >= 0 {
        //     if y[r] == x[c] {
        //         ans = string(x[c]) + ans
        //         r--
        //         c--
        //     } else {
        //         if dp[r - 1][c] > dp[r][c - 1] {
        //             r--
        //         } else {
        //             c--
        //         }
        //     }
        // }
        // Println(ans)
    }
}

Python: from sys import stdin
def lcs(x, y):
    m = len(x)
    n = len(y)
    c = [[0]*(m + 2) for a in range(n + 2)]
    for i in range(1, m + 1):
        for j in range(1, n + 1):
            if x[i-1] == y[j-1]:
                c[i][j] = (c[i - 1][j - 1]) + 1
            else:
                c[i][j] = max(c[i - 1][j], c[i][j - 1])
    return max(max(c))

n = int(input().rstrip())
strs = stdin.readlines()
ret = []
for i in range(n):
    # s1 = strs[i*2].rstrip()
    # s2 = strs[i*2+1].rstrip()
    ret.append(lcs(strs[i*2].rstrip(), strs[i*2+1].rstrip()))
print(*ret, sep="\n")

Python: def lcs(X, Y):
    row, colums = len(X) + 1, len(Y) + 1
    lcs_list = [[0 for y in range(colums)] for x in range(row)]
    for i in range(row):
        for j in range(colums):
            if i == 0 or j == 0:
                lcs_list[i][j] = 0
            elif X[i-1] == Y[j-1]:
                lcs_list[i][j] = lcs_list[i-1][j-1] + 1
            else:
                lcs_list[i][j] = max(lcs_list[i][j-1], lcs_list[i-1][j])
    return lcs_list[-1][-1]

import sys
n = int(input())
input_lines = sys.stdin.readlines()
for i in range(n):
    X = list(input_lines[2*i].rstrip())
    Y = list(input_lines[2*i+1].rstrip())
    print(lcs(X,Y))

Python: import sys


def len_lcs(s1, s2):
    """Find length of the longest common sequence(LCS) of strings s1 and s2.
    The complexity is ~MN.

    >>> len_lcs("abc", "abc")
    3
    >>> len_lcs("abcbdaba", "bdcaba")
    5
    """
    results = [0] * len(s1)

    for i, c2 in enumerate(s2):
        sec1, pr1 = 0, 0
        for j, c1 in enumerate(s1):
            if c1 == c2:
                match = 1
            else:
                match = 0
            pr2 = results[j]
            mval = max(sec1, pr2, pr1 + match)
            results[j] = mval
            sec1, pr1 = mval, pr2

    return results[-1]


def run():
    n = int(input())
    s = []
    for line in sys.stdin:
        s.append(line.strip())
    for i in range(0, 2*n, 2):
        print(len_lcs(s[i], s[i+1]))


run()

Python: m = int(input())
for i in range(m):
    str1 = input()
    str2 = input()
    A = [0 for j in range(len(str2)+1)]
    for j in range(len(str1)):
        for k in range(len(str2)):
            if(str1[j]==str2[k]):
                A[k+1] = A[k+1]+1
            else:
                if(A[k] > A[k+1]):
                    A[k+1] = A[k]
    print(A[-1])

Python: def length_of_lcs(x, y):
    n = len(y)
    #pre_row = [0] * (n + 1)
    cur_row = [0] * (n + 1)
    for x_c in x:
        prev_row = cur_row[:]
        for j, y_c in enumerate(y):
            if x_c == y_c:
                cur_row[j+1] = prev_row[j] + 1
            elif cur_row[j] > cur_row[j+1]:
                cur_row[j+1] = cur_row[j]

    return cur_row[n]


if __name__ == '__main__':
    N = int(input())
    for _ in range(N):
        x = input()
        y = input()
        print(length_of_lcs(x, y))

Python: def lcs(X, Y):
    dp = []
    for y in Y:
        bgn_idx = 0
        for i, cur_idx in enumerate(dp):
            chr_idx = X.find(y, bgn_idx) + 1
            
            if not chr_idx:
                break
            dp[i] = min(cur_idx, chr_idx)
            bgn_idx = cur_idx
        else:
            chr_idx = X.find(y, bgn_idx) + 1
            if chr_idx:
                dp.append(chr_idx)
    return len(dp)

q = int(input())
for i in range(q):
    X = input()
    Y = input()
    print(lcs(X, Y))

Python: import sys
sys.setrecursionlimit(10000)

def calc(x,y):
    i = len(x)
    j = len(y)
    if not d[i][j] == None:
        return d[i][j]
    else:
        if x[-1] == y[-1]:
            tmp = max(calc(x[:-1],y[:-1])+1,calc(x[:-1],y),calc(x,y[:-1]))
            d[i][j] = tmp
            return tmp
        else:
            tmp = max(calc(x[:-1],y),calc(x,y[:-1]))
            d[i][j] = tmp
            return tmp
        
q = int(input())
for i in range(q):
    x = input()
    y = input()
    d = [[0 if i == 0 or j == 0 else None for i in range(len(y)+1)] for j in range(len(x)+1)]
    print(calc(x,y))

Python: # -*- coding: utf-8 -*-
"""
Created on Fri May  4 20:33:37 2018
ALDS1_10_C
@author: maezawa
"""

def longest(x, y):
    m = len(x)
    n = len(y)
    c = [[0 for _ in range(n+1)] for _ in range(m+1)]
    for i in range(m):
        for j in range(n):
            #print(i,j)
            if x[i] == y[j]:
                c[i][j] = c[i-1][j-1] + 1
            else:
                c[i][j] = max(c[i-1][j], c[i][j-1])
    return c[m-1][n-1]

q = int(input())
for i in range(q):
    x = input()
    y = input()
    print(longest(x, y))

Python: def longest_common_subsequence(X, Y):
    X = " " + X
    Y = " " + Y

    length_X = len(X)
    length_Y = len(Y)

    c = [0] * length_Y

    for i in range(1, length_X):
        
        c_ = c[:]

        for j in range(1, length_Y):
            if X[i] == Y[j]:
                c[j] = c_[j - 1] + 1
            elif c_[j] < c[j - 1]:
                c[j] = c[j - 1]

    return c[-1]


q = int(input())


for _ in range(q):

    X = input()
    Y = input()

    print(longest_common_subsequence(X, Y))

Python: n=int(input())
ans=[]
for k in range(n):
    s1=input()
    s2=input()
    dp=[[0 for i in range(len(s2)+1)] for j in range(len(s1)+1)]
    for i in range(1,len(s1)+1):
        for j in range(1,len(s2)+1):
            if s1[i-1]==s2[j-1]:
                dp[i][j]=dp[i-1][j-1]+1
            else:
                dp[i][j]=max(dp[i-1][j],dp[i][j-1])


    ans.append(dp[len(s1)][len(s2)])
for a in ans:
    print(a)

Python: for _ in[0]*int(input()):
 X,Y=' '+input(),' '+input()
 m,n=len(X),len(Y)
 c=[[0]*n for _ in[0]*m]
 print(c)
 for i in range(1,m):
  for j in range(1,n):c[i][j]=(max(c[i-1][j],c[i][j-1]),1+c[i-1][j-1])[X[i]==Y[j]]
 print(c[m-1][n-1])