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 <algorithm>
#define rep(i, n) for(int i = 0; i < (int)(n); ++i)
#define REP(i, n) for(int i = 1; i < (int)(n); ++i)
using namespace std;

void solve(string S, string T) {
    vector<vector<int>> dp(S.size() + 1, vector<int>(T.size() + 1, 0));
    REP(i, S.size() + 1) REP(j, T.size() + 1) {
        if (S[i - 1] == T[j - 1]) dp[i][j] = max({dp[i - 1][j - 1] + 1, dp[i - 1][j], dp[i][j - 1]});
        else dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
    }
    cout << dp[S.size()][T.size()] << endl;
    return;
}

int main() {
    int q;
    cin >> q;
    rep(i, q) {
        string X, Y;
        cin >> X >> Y;
        solve(X, Y);
    }
    return 0;
}

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

#define rep(i,x,y) for(int i=(x);i<(y);++i)
#define mp(a,b) make_pair((a),(b))
#define debug(x) #x << "=" << (x)
 
#ifdef DEBUG
#define _GLIBCXX_DEBUG
#define dump(x) std::cerr << debug(x) << " (L:" << __LINE__ << ")" << std::endl
#else
#define dump(x)
#endif

typedef long long int ll;
typedef pair<int,int> pii;
//template<typename T> using vec=std::vector<T>;

const int INF=1<<30;
const long long int INFLL=1LL<<58;
const double EPS=1e-9;
const int dx[]={1,0,-1,0},dy[]={0,1,0,-1};

template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec){
	os << "[";
	for (const auto &v : vec) {
		os << v << ",";
	}
	os << "]";
	return os;
}

void solve_(){
     string a,b;
    cin >> a >> b;
    
    static int dp[1000][1000];
    fill_n((int*)dp,1000*1000,0);
    
    rep(i,0,a.size()){
        rep(j,0,b.size()){
            if(i!=0) dp[i][j]=dp[i-1][j];
            if(j!=0) dp[i][j]=max(dp[i][j],dp[i][j-1]);
            
            if(a[i]!=b[j]) continue;
            
            if(i==0||j==0) dp[i][j]=1;
            else dp[i][j]=max(dp[i][j],dp[i-1][j-1]+1);
        }
    }
    
    cout << dp[a.size()-1][b.size()-1] << endl;
}

void solve(){
    int n;
    cin >> n;
    rep(i,0,n) solve_();
}

int main(){
	std::ios::sync_with_stdio(false);
	std::cin.tie(0);
	solve();
	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <string>
#include <list>
#include <stack>
#include <queue>
#include <algorithm>
#include <utility>
#include <vector>
#include <map>

using namespace std;

int main()
{
    int N;
    int data[1001][1001]={};
    cin>>N;
    string str1,str2;
    for(int i=0;i<N;i++){
        cin>>str1>>str2;
        for(int i=0;i<str1.length();i++){
            for(int j=0;j<str2.length();j++){
                if(str1[i]==str2[j]){
                    data[i+1][j+1]=data[i][j]+1;
                }else{
                    data[i+1][j+1]=data[i+1][j]>data[i][j+1]?data[i+1][j]:data[i][j+1];
                }
            }
        }
        cout<<data[str1.length()][str2.length()]<<endl;
    }
}

C++: /* 
*  入力された二つの文字列から最長共通部分列を求める。
*  二次元配列使用、動的計画法を利用する 
*/

#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]; // 二次元配列
	int m = X.size(); // 文字列１の長さ
	int n = Y.size(); // 文字列２の長さ
	int maxl = 0; // 文字列の最長の長さ
	X = ' ' + X; // X[0]に空白を挿入
	Y = ' ' + Y; // Y[0]に空白を挿入

	c[0][0] = 0;
	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]);
		}
	}

	// 配列c[][]の中身確認
	/*for (int i = 0; i <= m; i++) {
		for (int j = 0; j <= n; j++) {
			cout << c[i][j] << ", ";
		}
		cout << endl;
	}*/

	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 <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <fstream>
#include <iostream>
#include <map>
#include <queue>
#include <string>
#include <stack>
#include <vector>
#include <set>
#include <tuple>
#include <utility>
#include <functional>
using namespace std;
typedef long long ll;
typedef pair<int,int> P;

int main(){
	int q;
	cin >> q;
	vector<int> ans(q);
	for(int i = 0;i < q;i++){
		string s,t;
		cin >> s >> t;
		int n = s.size();
		int m = t.size();

		vector<vector<int>> dp(n+1,vector<int>(m+1,0));

		for(int i = 0;i < n;i++){
			for(int j = 0;j < m;j++){
				if(s[i] == t[j]){
					dp[i+1][j+1] = max({dp[i][j+1],dp[i+1][j],dp[i][j]+1});
				}
				else{
					dp[i+1][j+1] = max(dp[i+1][j],dp[i][j+1]);    
				}
			}
		}
		ans[i] = dp[n][m];
	}

	for(int a:ans)cout << a << endl;
}

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

using namespace std;

int solve(string s1, string s2){
    int L[s1.size()+1][s2.size()+1];
    for(int i=0;i<=s1.size();i++){
        for(int j=0;j<=s2.size();j++){
            if(i==0 || j==0){
                L[i][j]=0;
            }
            else if(s1[i] == s2[j]){
                L[i][j] = 1 + L[i-1][j-1];
            }
            else{
                L[i][j] = max(L[i][j-1],L[i-1][j]);
            }
        }
    }
    return L[s1.size()][s2.size()];
}

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