Go: package main

import (
	"fmt"
)

func main() {
	var q int
	fmt.Scan(&q)

	for i := 0; i < q; i++ {
		var x, y string
		fmt.Scan(&x)
		fmt.Scan(&y)

		xs := []rune(x)
		ys := []rune(y)

		xn := len(xs)
		yn := len(ys)
		dp := make([][]int, xn+1)
		for j := 0; j <= xn; j++ {
			dp[j] = make([]int, yn+1)
		}

		for j := 1; j <= xn; j++ {
			for k := 1; k <= yn; k++ {
				dp[j][k] = max(dp[j-1][k], dp[j][k-1])
				if xs[j-1] == ys[k-1] {
					dp[j][k] = max(dp[j][k], dp[j-1][k-1] + 1)
				} else {
					dp[j][k] = max(dp[j][k], dp[j-1][k-1])
				}
			}
		}
		fmt.Println(dp[xn][yn])
	}
}

func max(a, b int) int {
	if a < b {
		return b
	} else {
		return a
	}
}

C++: // ????????±?????¨??????
#include <iostream>
#include <utility>
#include <string>
#include <algorithm>
#include <set>
#include <string>
#define MAX 1050
using namespace std;
int q,length_x,length_y;
int dp[MAX][MAX];
string X,Y;
int init_func () {
  for (int i=0; i<MAX ; i++)
    for (int j=0; j<MAX ; j++)
      dp[i][j] = 0;
}

int solve () {
  // dp = {0}
  // dp?????¨?????????X????¨????Y??¨??????
  for (int tate=1; tate<=length_x ; tate++)
    for (int yoko=1; yoko<=length_y ; yoko++)
      if (X[tate-1] == Y[yoko-1]) dp[tate][yoko] = 1 + dp[tate-1][yoko-1];
      else dp[tate][yoko] = max(dp[tate-1][yoko],dp[tate][yoko-1]);
  
  return dp[length_x][length_y];
}

int main(){
  cin >> q;
  for (int i=0; i<q; i++) {
    cin >> X >> Y;
    length_x = X.length();
    length_y = Y.length();
    init_func();
    cout << solve() << endl;
  }
  return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<string>

using namespace std;

int lcs (string x, string y) {

    int m, n, c[1001][1001], i, j, maxl = 0;

    m = x.size();
    n = y.size();

    x = ' ' + x;
    y= ' ' + y;

    for (i = 0; i <= m; i++) {
        c[i][0] = 0;
    }
    for (j = 1; j <= n; j++) {
        c[0][j] = 0;
    }

    for (i = 1; i <= m; i++) {
            for (j = 1; j <= n; j++) {

                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]);
                }

                maxl = max (max, c[i][j]);

            }
    }

    return maxl;

}



int main () {

    int N, i;
    string x, y;

    cin >> N;

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

    }

    return 0;

}

C++: #include<iostream>
#include<string>
#include<algorithm>
using namespace std;
static const int N =1000;
int lcs(string, 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 = 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] = mx(c[i - 1][j], c[i][j = 1]);
      }
      maxl = max(mxl, 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 << lcs8s1, s2) << endl;
  }
  return 0;
}

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();
  
  for (int i = 0; i < m; i++) {
    for (int j = 0; j < n; j++) {
      if (X[i] == Y[j]) 
        if (i == 0 || j == 0) 
          c[i][j] = 1;
        else 
          c[i][j] = c[i - 1][j - 1] + 1;
      else
        if (i != 0 && j != 0) 
          c[i][j] = max(c[i][j - 1], c[i - 1][j]);
        else
          c[i][j] = 0;
    }
  }
  return c[m - 1][n - 1];
}

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>
#include<algorithm>
using namespace std;

int lcs(string X, string Y){
  int c[1001][1001];
  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 = 1;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<bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (n); ++i)

using namespace std;
using ll = long long;
using v1 = vector<int>;
using vl = vector<long long>;
using v2 = vector<vector<int>>;
using v3 = vector<vector<char>>;

int N, M;
string s1, s2;

int lcs(string x, string y){
	int c[1001][1001];
	N = s1.size();
	M = s2.size();
	int maxl = 0;
	x = ' ' + x;
	y = ' ' + y;
	rep(i, N) c[i][0] = 0;
	rep(i, M) c[0][i] = 0;
	for(int i = 1; i<=N;i++){
		for(int j = 1; j<=M; j++){
			if(x[i] == y[j]){
				c[i][j] = c[i-1][j-1]+1;
			}else{
				c[i][j] = max(c[i][j-1], c[i-1][j]);
			}
			maxl = max(maxl, c[i][j]);
		}
	}
	return maxl;
}

int main(){
	int n;
	cin >> n;
	rep(i, n){
		cin >> s1 >> s2;
		cout << lcs(s1,s2) << 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 = 1; i <= m; i++) {
        c[i][0] = 0;
    }
    for (int j = 1; 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(int argc, char const* argv[])
{
    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 <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int dp[1010][1010];

int main(){
    int q; cin >> q;
    rep(i,q){
        string x,y; cin >> x >> y;
        for(int i = 0; i < x.size(); i++){
            for(int j = 0; j < y.size(); j++){
                if(x[i]==y[j]) dp[i+1][j+1] = dp[i][j] + 1;
                else dp[i+1][j+1] = max(dp[i+1][j],dp[i][j+1]);
            }
        }
        cout << dp[x.size()][y.size()] << endl;
    } 
    return 0;
}

C++: #include <iostream>
#include <string>

/*int LCS(std::string str1, std::string str2, int i, int j){
  if(str1[i] == str2[j]){
    return 1;
  }
  else{
    return 0;
  }
 }
*/

int max(int a, int b, int c){
  int m = a;
  if(b > m){
    m = b;
  }
  if(c > m){
    m = c;
  }
  return m;
}

int main(){
  int q;
  std::cin >> q;
  //int ans[q];
  std::string str1, str2;
  for(int z=0; z<q; z++){
    std::cin >> str1 >> str2;
    int l1 = str1.size();
    int l2 = str2.size();
    int DP[l1+1][l2+1];

    for(int i=0; i<=l1; i++){
      DP[i][0] = 0;
    }
    for(int j=0; j<=l2; j++){
      DP[0][j] = 0;
    }

    for(int i=1; i<=l1; i++){
      for(int j=1; j<=l2; j++){
	if(str1[i-1] == str2[j-1]){
	  DP[i][j] = max(DP[i-1][j], DP[i][j-1], DP[i-1][j-1] + 1);
	}
	else{
	  DP[i][j] = max(DP[i-1][j], DP[i][j-1], DP[i-1][j-1]);
	}
      }
    }
    //ans[z] = DP[l1][l2];
    std::cout << DP[l1][l2] << std::endl;
  }

  /*for(int z=0; z<q; z++){
    std::cout << ans[z] << std::endl;
    }*/
  return 0;
}