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 <vector>
using namespace std;

int max(int a,int b);

int main() {
  int q;
  cin >> q;
  for (int i=0;i<q;++i) {
    string str1,str2;
    cin >> str1 >> str2;
    int size1 = str1.size();
    int size2 = str2.size();
    int matrix[size1+1][size2+1];
    for (int j=0;j<=size1;++j)
      matrix[j][0] = 0;
    for (int j=0;j<=size2;++j)
      matrix[0][j] = 0;
    for (int j=1;j<=size1;++j) {
      for (int k=1;k<=size2;++k) {
	if (str1[j-1]==str2[k-1]) {
	  matrix[j][k] = 1 + matrix[j-1][k-1];
	}
	else {
	  matrix[j][k] = max(matrix[j][k-1],matrix[j-1][k]);
	}
      }
    }
    cout << matrix[size1][size2] << endl;
  }
}

int max(int a,int b) {
  if (a>b)
    return a;
  else
    return b;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<cstdlib>
#include <cmath>
#include<stdio.h>
#include<queue>
#define MAX 1000000000000000000LL
long long inf=1000000007;
using namespace std;
    int H,A[2000001];

int lcs(string X,string Y){
    int  c[1001][1001];
    long long m=X.size();
    long long  n=Y.size();
    int maxl=0;
    X=' '+X;
    Y=' '+Y;
    for(int i=1; i<=m; i++){
        c[i][0]=0;
    }
    for(int i=1; i<=n; i++)c[0][i]=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]);
            }
            maxl=max(maxl,c[i][j]);
        }
    }
    return maxl;
}
int main(){
    string s1,s2;
    int n;cin>>n;
    for(int i=0; i<n; i++){
        cin>>s1>>s2;
        cout<<lcs(s1,s2)<<endl;
    }
    return 0;

 
}

C++: #include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
char x[1007], y[1007];
int dp[1007][1007];
int main() {
    int q;
    scanf("%d", &q);
    while (q--) {
    	scanf("%s%s", x, y);
    	int xlen = strlen(x), ylen = strlen(y);
    	for (int i = 1; i <= xlen; i++) {
    		for (int j = 1; j <= ylen; j++) {
    			if (x[i - 1] == y[j - 1]) dp[i][j] = dp[i - 1][j - 1] + 1;
    			else dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
			}
		}
		printf("%d\n", dp[xlen][ylen]);
	}
    return 0;
}

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

int Lcs(string X, string Y) {
  vector< vector<int> > dp(X.size() + 1, vector<int>(Y.size() + 1));
  X = ' ' + X, Y = ' ' + Y;
  for (int i = 1; i <= X.size() - 1; ++i) {
    for (int j = 1; j <= Y.size() - 1; ++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[X.size() - 1][Y.size() - 1];
}

int main() {
  int q;
  cin >> q;
  for (int i = 0; i < q; ++i) {
    string X, Y;
    cin >> X >> Y;
    cout << Lcs(X, Y) << endl;
  }
}

C++: #include<iostream>
#include<string>
#include<algorithm>
using namespace std;
static const int N = 1000;
 
int lcs(string X, string Y) {
    int c[N + 1][N + 1];
    int m = X.size();
    int n = Y.size();
    int maxl = 0;
    X = " " + X;
    Y = " " + Y;
    for(int i = 0; i <= m; i++) c[i][0] = 0;
    for(int j = 0; j <= n; j++) c[0][j] = 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]);
        }
        maxl = max(maxl, c[i][j]);
        }
    }
     
    return maxl;
}  
 
int main() {
    string s1, s2;
    int n;
    cin >> n;
    for(int i = 0; i < n; i++) {
        cin >> s1 >> s2;
        cout << lcs(s1, s2) << endl;  
    }
     
    return 0;
}

C++: #include<iostream>
#include<string>
using namespace std;

#define MAX 150
#define MAXL 1000

int C[MAXL+1][MAXL+1];

int lec(string X,string Y)
{
    int XL = X.length();
    int YL = Y.length();
    for(int i=0;i<XL;i++)
        C[i][0] = 0;
    for(int i=0;i<=YL;i++)
        C[0][i] = 0;
    for(int i=0;i<=XL;i++)
    {
        for(int j=0;j<YL;j++)
        {
            if(X[i]==Y[j])
            {
                C[i+1][j+1] = C[i][j]+1;
            }
            else if(C[i][j+1] > C [i+1][j])
            {
                C[i+1][j+1] = C[i-1][j+1];
            }else{
                C[i+1][j+1] = C[i+1][j];
            }
        }
    }
    return C[XL][YL];
}

int main()
{
    int q;
    string x,y;
    cin>>q;
    for(int i=0;i<q;i++)
    {
        cin>>x>>y;
        cout<<lec(x,y)<<endl;
    }
    return 0;
}

C++: #include <iostream>
#include <string>
#include <cstring>
#include <algorithm>
using namespace std;
int dp[1001][1001];

int main(){
	int n; cin >> n;
	while (n--){
		string X, Y; cin >> X >> Y;
		memset(dp, 0, sizeof(dp));
		for (int i = 1; i <= X.size(); ++i){
			for (int j = 1; j <= Y.size(); ++j){
				if (X[i-1] == Y[j-1]) dp[i][j] = max(dp[i][j-1],max(dp[i-1][j],dp[i-1][j-1]+1));
				else dp[i][j] = max(dp[i][j - 1], dp[i - 1][j]);
			}
		}
		cout << dp[(int)X.size()][(int)Y.size()] << '\n';
	}
}