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)
    }
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <set>
#include <algorithm>
#include <array>
#include <complex>
#include <utility>
#include <map>
#include <inttypes.h>

int LCS(std::string s,std::string t){
    int n,m,c[n+1][m+1];
    n=s.size();
    m=t.size();
    int maxlen=0;
    for(int i=0;i<=n;i++){
        c[i][0]=0; 
    }
    for(int i=0;i<=m;i++){
        c[0][i]=0;
    }
    for(int i=1;i<n;i++){
        for(int j=1;j<m;j++){
            if(s[i]==t[i]){
                c[i][j]=c[i-1][j-1]+1;
            }else{
                c[i][j]=std::max(c[i-1][j],c[i][j-1]);
            }
            maxlen=std::max(c[i][j],maxlen);
        }
    }
    return maxlen;
}
int main(){
	int N;
    
    std::cin >> N;
    std::string s1,s2;
    for(int i=0;i<N;i++){
        std::cin >> s1 >> s2;
        std::cout << LCS(s1,s2) <<std::endl;
    }
        
    
    return 0;
}

C++: #include<iostream>
#include<string>
#include<algorithm>
using namespace std;
#define maxn 1001

int lac(string x, string y) {
	int c[maxn][maxn];
	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()
{
	int n;
	cin >> n;
	string x, y;
	for (int i = 0; i < n; i++) {
		cin >> x;
		cin >> y;
		cout << lac(x, y) << endl;
	}
	return 0;
}

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

int main() {
	int q;
	std::cin >> q;
	
	for (int i = 0; i < q; i++) {
		std::string s1, s2;
		std::cin >> s1 >> s2;
		std::vector<int> ref(s2.size(), 0);
		for (int j = 0; j < s1.size(); j++) {
			std::vector<int> vec = ref;
			for (int k = 0; k < s2.size(); k++) {
				if (s1[j] == s2[k]) {
					int al = k == 0 ? 0 : ref[k - 1];
					int a = ref[k];
					vec[k] = std::max(al + 1, a);
				}
				else {
					int l = k == 0 ? ref[0] : vec[k - 1];
					int a = ref[k];
					vec[k] = std::max(l, a);
				}
			}
			ref = vec;
		}
		std::cout << ref[s2.size() - 1] << std::endl;
	}
}

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

int main(){
  int n;
  char x[1001],y[1001];
  int dp[1010][1010];
  //load n;
  cin >>n;
  for(int i=0;i<n;i++){
    //load string
    scanf("%s",x);
    scanf("%s",y);
    //dp
    for(int j=0;j<strlen(x);j++){
      for(int k=0;k<strlen(y);k++){
	if(x[j]==y[k]){
	  dp[j+1][k+1]=dp[j][k]+1;
	}

	else{
	  if(dp[j][k+1]>dp[j+1][k]){
	    dp[j+1][k+1]=dp[j][k+1];
	  }

	  else{
	    dp[j+1][k+1]=dp[j+1][k];
	  }


	}
      }
    }
    cout <<dp[strlen(x)][strlen(y)]<<endl;
  }



  return 0;
}

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

#define REP(i, n) for(int i = 0; i < (n); i++)

string str1, str2;
int dp[1001][1001];
int k;

int solve(int i, int j)
{
  if(dp[i][j] > 0)
    return dp[i][j];
  if(i == str1.size() || j == str2.size()){
    if(i != str1.size()){
      return solve(i + 1, k);
    }else{
      return 1;
    }
  }
  if(str1[i] == str2[j]){
    k = j + 1;
    dp[i][j] = solve(i + 1, j + 1);
    return dp[i][j] + 1;
  }else{
    return solve(i, j + 1);
  }
}

int main()
{
  int q, n, ans = 0;
  cin >> q;
  cin.ignore();
  fill(&dp[0][0], &dp[1001][0], -1);
  REP(i, q){
    getline(cin, str1);
    getline(cin, str2);
    if(str1.size() < str2.size())
      swap(str1, str2);
    REP(i, str1.size()){
      n = solve(i, 0) - 1;
      ans = (n > ans) ? n : ans;
    }
    cout << ans << endl;
    ans = 0;
  }
}