Go: package main

import (
	"fmt"
	"os"
	"strconv"
	"bufio"
	"strings"
	"sort"
)

// define
var (
	sc = bufio.NewScanner(os.Stdin)
)

func bordersInt(in_map [][]int, invalid int) [][]int{
	H, W := len(in_map), len(in_map[0])
	out_map := make([][]int, H+2)
	for h:=0; h<H+2; h++ {
		out_map[h] = make([]int, W+2)
		for w:=0; w<W+2; w++ {
			out_map[h][w] = invalid
		}
	}
	for h:=0; h<H; h++{
		for w:=0; w<W; w++{
			out_map[h+1][w+1] = in_map[h][w] 
		}
	}
	return out_map
}

func bordersString(in_map [][]string, invalid string) [][]string{
	H, W := len(in_map), len(in_map[0])
	out_map := make([][]string, H+2)
	for h:=0; h<H+2; h++ {
		out_map[h] = make([]string, W+2)
		for w:=0; w<W+2; w++ {
			out_map[h][w] = invalid
		}
	}
	for h:=0; h<H; h++{
		for w:=0; w<W; w++{
			out_map[h+1][w+1] = in_map[h][w] 
		}
	}
	return out_map
}

func scanIntLine(len int) []int{
	arr := make([]int, len)
	for i:=0; i<len; i++{
		sc.Scan()
		tmp, err := strconv.Atoi(sc.Text())
		if err == nil{
			arr[i] = tmp
		}
	}
	return arr
}

func scanStringLine(len int) []string{
	arr := make([]string, len)
	for i:=0; i<len; i++{
		sc.Scan()
		arr[i] = sc.Text()
	}
	return arr
}

func scanIntSplit(len int) []int{
	arr := make([]int, len)
	sc.Scan()
	for i, v := range strings.Split(sc.Text(), " "){
		tmp, err := strconv.Atoi(v)
		if err == nil{
			arr[i] = tmp
		}
	}
	return arr
}

func maxInt(args... int) int{
	sort.Ints(args)
	return args[len(args)-1]
}

func f() {
	var S, T string
	fmt.Scan(&S)
	fmt.Scan(&T)
	lenS, lenT := len(S), len(T)
	dp := make([][]int, lenS+1)
	for i:=0; i<lenS+1; i++ {
		dp[i] = make([]int, lenT+1)
	}
	for i:=1; i<lenS+1; i++ {
		for j:=1; j<lenT+1; j++ {
			if S[i-1] == T[j-1] {
				dp[i][j] = maxInt(dp[i-1][j-1]+1, dp[i-1][j], dp[i][j-1])
			} else {
				dp[i][j] = maxInt(dp[i-1][j], dp[i][j-1])
			}
		}
	}
	fmt.Println(dp[lenS][lenT])
}

func main(){
	var n int 
	fmt.Scan(&n)
	for i:=0; i<n; i++ {
		f()
	}
}

Python: for _ in range(int(input())):
    X = input()
    Y = input()
    dp = [[0] * (len(Y)+1) for x in range(len(X)+1)]
    for x in range(1, len(X) + 1):
        pre = dp[x-1]
        tmp = dp[x]
        for y in range(1, len(Y) + 1):
            if X[x-1] == Y[y-1]:
                tmp[y] = pre[y-1] + 1
            else:
                tmp[y] = max(tmp[y-1], pre[y])
    print(dp[-1][-1])

Python: def findlcs(x, y):
    dp = [0]*(len(y)+1)

    for c in x:
        tmp = dp[:]
        for j in range(len(y)):
            if c == y[j]:
                dp[j+1] = tmp[j] + 1
            elif dp[j+1] < dp[j]:
                dp[j+1] = dp[j]

    return dp[-1]


q = int(input())
for k in range(q):
    X = input()
    Y = input()
    print(findlcs(X, Y))

Python: def LCS(X, Y):
    n = len(X)
    m = len(Y)
    T = [0]*(n+1)
    
    for j in range(m):
        T_old = T[:]
        c = Y[j]
        for i in range(n):
            if X[i] == c:
                T[i] = T_old[i-1] + 1
            elif T[i-1] > T[i]:
                T[i] = T[i-1]            
    return T[len(X)-1] 



q = int(input())
for cnt in range(q):
    X = input()
    Y = input()
    print(LCS(X, Y))

Python: def lcs(x, y):
    m = len(x)
    n = len(y)
    c = [[0] * 1001 for i in range(1002)]
    x = " " + x
    y = " " + y
    maxl = 0
    for i in range(1, m + 1):
        for j in range(1, n + 1):
            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])
            maxl = max(maxl, c[i][j])
    return maxl

if __name__ == '__main__':
    n = int(input().rstrip())
    for i in range(n):
        s1 = input().rstrip()
        s2 = input().rstrip()
        print(lcs(s1, s2))

Python: #JOI
def main():
    X=input()
    Y=input()
    dp=[[0 for y in range(1+len(Y))] for x in range(1+len(X))]
    for x in range(len(X)):
        for y in range(len(Y)):
            now=0
            dp[x][y]=max(dp[x-1][y],dp[x][y-1])
            for x1 in range(Y[:y+1].count(X[x])):
                idx=Y[now:y+1].index(X[x])
                now=idx+1
                dp[x][y]=max(dp[x-1][idx-1]+1,dp[x][y])
            now=0
            for y1 in range(X[:x+1].count(Y[y])):
                idx=X[now:x+1].index(Y[y])
                now=idx+1
                dp[x][y]=max(dp[idx-1][y-1]+1,dp[x][y])
    print(dp[len(X)-1][len(Y)-1])
for i in range(int(input())):
    main()

Python: def lcs(x, y):
    a = len(x)
    b = len(y)
    c1 = [0] * (b + 1)
    for i in range(a):
        c2 = c1[:]
        for j in range(b):
            if x[i] == y[j]:
                c1[j+1] = c2[j] + 1
            elif c1[j+1] < c1[j]:
                c1[j+1] = c1[j]
    return c1[-1]


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

Python: # -*- coding:utf-8 -*-
import sys


def search(x, y):
    x_length = len(x)
    y_length = len(y)
    memo = [[0] * (y_length + 1) for i in range(x_length + 1)]
    for i, ch_x in enumerate(x, 1):
        row = memo[i]
        pre_row = memo[i-1]
        for j, ch_y in enumerate(y, 1):
            if ch_x == ch_y:
                row[j] = pre_row[j-1] + 1
            else:
                row[j] = max(pre_row[j], row[j-1])
    return memo[-1][-1]


if __name__ == "__main__":
    n = int(input())
    strs = [list(val) for val in sys.stdin.read().splitlines()]
    result = [search(strs[i*2], strs[i*2+1]) for i in range(n)]
    print(*result, sep="\n")

Python: e=input
for _ in[0]*int(e()):
 X,z=e(),[]
 for y in e():
  s=i=0
  for k in z:
   t=X.find(y,s)+1
   if t<1:break
   if t<k:z[i]=t
   s=k;i+=1
  else:
   t=X.find(y,s)+1
   if t:z+=[t]
 print(len(z))

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
    """
    len1 = len(s1)
    len2 = len(s2)
    if len1 == 0 or len2 == 0:
        return 0

    primary = [0] * len1
    secondary = [0] * len1

    for i in range(len2):
        for j in range(len1):
            if s1[j] == s2[i]:
                match = 1
            else:
                match = 0
            if j == 0:
                secondary[j] = max(primary[j], match)
            else:
                sc1, p1, p2 = secondary[j-1], primary[j-1] + match, primary[j]
                if sc1 > p1:
                    if p1 > p2:
                        secondary[j] = sc1
                    elif p2 > sc1:
                        secondary[j] = p2
                    else:
                        secondary[j] = sc1
                else:
                    if sc1 > p2:
                        secondary[j] = p1
                    elif p1 > p2:
                        secondary[j] = p1
                    else:
                        secondary[j] = p2
                # secondary[j] = max(secondary[j-1], primary[j],
                #                    primary[j-1] + match)

        primary, secondary = secondary, primary

    return primary[len1-1]


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


if __name__ == '__main__':
    run()