Go: package main

/*
最長共通部分列
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"
)

func larger(l, r int) int {
	if l > r {
		return l
	}
	return r
}

var memo [1001][1001]int

func countLCS(x, y string) int {
	x = " " + x
	y = " " + y
	max := 0
	for xi := 1; xi < len(x); xi++ {
		for yi := 1; yi < len(y); yi++ {
			if x[xi] == y[yi] {
				memo[xi][yi] = memo[xi-1][yi-1] + 1
			} else {
				memo[xi][yi] = larger(memo[xi-1][yi], memo[xi][yi-1])
			}
			max = larger(max, memo[xi][yi])
		}
	}
	return max
}

func main() {
	scanner := makeScanner(1024)
	q := eGetInt(scanner)
	for i := 0; i < q; i++ {
		x := eGetLine(scanner)
		y := eGetLine(scanner)
		fmt.Println(countLCS(x, y))
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}
func min(a []int) int {
	m := a[0]
	for _, v := range a {
		if v < m {
			m = v
		}
	}
	return m
}

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

C++: #include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<algorithm>
#include<bitset>
#include<vector>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<iomanip>
#include <functional>
using namespace std;
typedef long long ll;
const int mod = 1000000007;
const int INF = 1 << 28;
//cout << fixed << std::setprecision(9)
//memset(a, 0, sizeof(a));
//--------------------------

int lcs(string x, string y)
{
	int dp[1100][1100];
	memset(dp, 0, sizeof(dp));

	x = " " + x;
	y = " " + y;
	int n = x.size();
	int m = y.size();


	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= m; j++) {
			if (x[i] == y[j]){
				dp[i][j] = dp[i - 1][j - 1] + 1;
			}
			else {
				dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
			}
		}
	return dp[n][m];
}

int main()
{
	int q;
	for (int i = 0; i < q; i++) {
		string s1, s2;
		cout << lcs(s1, s2) << endl;
	}

	return 0;
}

C++: #include<iostream>
#include<vector>
#include<string>
#include<cstdio>
#include<set>
#include<algorithm>
#define ll long long
using namespace std;

int dp[1001][1001];
int main() {
	int b;
	scanf("%d", &b);
	char e[1001];
	char f[1001];
	for (int c = 0; c < b; c++) {
		scanf("%s%s", e, f);
		for (int g = 0; g <= strlen(e); g++) {
			for (int h = 0; h <= strlen(f); h++) {
				dp[g][h] = 0;
			}
		}
		for (int g = 0; g < strlen(e); g++) {
			for (int h = 0; h < strlen(f); h++) {
				if (e[g] == f[h]) {
					dp[g+1][h+1] = dp[g][h] + 1;
				}
				else {
					dp[g+1][h+1] = max(dp[g][h + 1], dp[g + 1][h]);
				}
			}
		}
		printf("%d\n", dp[strlen(e)][strlen(f)]);
	}
}

C++: #include<bits/stdc++.h>
using namespace std;

int lcs(string s1,string s2){
  int c[s1+1][s2+1];
  int m=s1.size(),n=s2.size();
  int mx=0;
  s1=' '+s1;
  s2=' '+s2;
  for(int i=1;i<=m;i++){
    for(int j=1;j<=n;j++){
      if(s1[i]==s2[j]){
	c[i][j]=c[i-1][j-1]+1;
      }else{
	c[i][j]=max(c[i-1][j],c[i][j-1]);
      }
      mx=max(mx,c[i][j]);
    }
  }
  return mx;
}


int main(){
  int q;
  string s1,s2;
  cin>>q;
  for(int i=0;i<q;i++){
    cin>>s1>>s2;
    cout<<lcs(s1,s2)<<endl;
  }
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

template < typename T > inline void chmax(T &a, T b) { a = max(a, b); }

void solve()
{
    string S, T;
    cin >> S >> T;
    
    vector < vector < int > > dp(S.size() + 1, vector < int >(T.size() + 1, 0));

    for ( int i = 0; i <= S.size(); i++ ) {
        for ( int j = 0; j <= T.size(); j++ ) {
            if ( i < S.size() ) chmax(dp[i + 1][j], dp[i][j]);
            if ( j < T.size() ) chmax(dp[i][j + 1], dp[i][j]);
            if ( i < S.size() && j < T.size() && S[i] == T[j] ) chmax(dp[i + 1][j + 1], dp[i][j] + 1);
        }
    }
    cout << dp[S.size()][T.size()] << endl;
}

int main()
{
    int Q;
    cin >> Q;
    while ( Q-- ) solve();
    return ( 0 );
}

C++: #include"bits/stdc++.h"
using namespace std;

int lcs(string x, string y)
{
	int m = x.size();
	int n = y.size();
	x = ' ' + x;		//x[0]に空白を挿入
	y = ' ' + y;		//y[0]に空白を挿入
	vector<vector<int>> c(m + 1, vector<int>(n + 1, 0));

	for (int i = 1; i <= m; i++)
	{
		for (int j = 1; j <= n; 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][n];
}

int main(void)
{
	int N;
	string x, y;
	cin >> N;

	for (int i = 0; i < N; i++)
	{
		cin >> x >> y;
		cout << lcs(x, y) << endl;
	}

	return 0;
}