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 <bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin >> n;
    for(int q=0;q<n;q++){
        string x,y;
        cin >>x >> y;
        int dp[1002][1002];
        memset(dp,-1, sizeof(dp));
        dp[0][0] = 0;
        for(int i=0;i<x.size()+1;i++){
            for(int j=0;j<y.size()+1;j++){
                if (i < x.size() && j < y.size() && x[i] == y[j]){
                dp[i+1][j+1] = max(dp[i+1][j+1], dp[i][j] + 1);
                }
                dp[i][j+1] = max(dp[i][j+1],dp[i][j]);
                dp[i+1][j] = max(dp[i+1][j],dp[i][j]);
            }
        }
        cout << dp[x.size()][y.size()] << endl;
    }
}

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

int lcs(std::string x, std::string y) {
	if (x.length() > y.length()) { x.swap(y); }
	int lx = x.length(), ly = y.length();
	std::vector<std::vector<int>> dp(ly, std::vector<int>(lx));

	dp.at(0).at(0) = (int)(x[0] == y[0]);
	for (int i = 1; i < ly; i++) {
		dp.at(i).at(0) = std::max(dp.at(i - 1).at(0), (int)(x[0] == y[i]));
		if (i < lx) { dp.at(0).at(i) = std::max(dp.at(0).at(i - 1), (int)(x[i] == y[0])); }
	}

	for (int i = 1; i < lx; i++) {
		dp.at(i).at(i) = std::max(dp.at(i - 1).at(i), dp.at(i).at(i - 1));
		if (x[i] == y[i]) { dp.at(i).at(i) = dp.at(i - 1).at(i - 1) + 1; }
		
		for (int t = i + 1; t < ly; t++) {
			if (x[i] == y[t]) { dp.at(t).at(i) = dp.at(t - 1).at(i - 1) + 1; } 
			else { dp.at(t).at(i) = std::max(dp.at(t).at(i - 1), dp.at(t - 1).at(i)); }

			if (t < lx) {
				if (x[t] == y[i]) { dp.at(i).at(t) = dp.at(i - 1).at(t - 1) + 1; } 
				else { dp.at(i).at(t) = std::max(dp.at(i).at(t - 1), dp.at(i - 1).at(t)); }

			}
		}
	}
	return dp.at(ly-1).at(lx-1);
}

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

C++: #include <bits/stdc++.h>
using namespace std;
string s1,s2;
// 公共
int dp[1005][1005];
void solve(){
	memset(dp,0,sizeof(dp));
	for(int i=1;i<s1.length();i++)
		for(int j=1;j<=s2.length();j++)
			dp[i][j]=(s1[i]==s2[j]?dp[i-1][j-1]+1:max(dp[i-1][j],dp[i][j-1]));
	cout<<dp[s1.length()-1][s2.length()-1]<<endl;
}
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
//	freopen("a.txt","r",stdin);
	int T;cin>>T;
	while(T--){
		cin>>s1>>s2;
		s1=" "+s1;
		s2=" "+s2;
		solve();		
	}
	return 0;
}

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


int main(){
  string X, Y;
  int q;
  cin >> q;
  for(int i = 0; i < q; i++){
    cin >> X >> Y;
    vector<vector<int> > dp(X.size(), vector<int>(Y.size(), 0));
    for(int i = 0; i < X.size(); i++){
      for(int j = 0; j < Y.size(); j++){
        if(X[i] == Y[j]){
          if(i == 0 || j == 0)dp[i][j] = 1;
          else dp[i][j] = dp[i - 1][j - 1] + 1;
        }else {
          if(i == 0 && j == 0)dp[i][j] = 0;
          else if(i == 0 && j != 0)dp[i][j] = dp[i][j - 1];
          else if(i != 0 && j == 0)dp[i][j] = dp[i - 1][j];
          else dp[i][j] = max(dp[i][j - 1], dp[i - 1][j]);
        }
      }
    }
    cout << dp[X.size() - 1][Y.size() - 1] << 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 = 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<iostream>
#include<cstdio>

using namespace std;

int maxa[1000];
int main(){
  int n;
  int k;
  int count;
  cin>>n;
  char X[1001];
  char Y[1001];
  for(int i=0;i<n;i++){
    cin>>X;
    cin>>Y;
    k=0;
    for(int a=0;X[a]!='\0';a++){
    count=0;
      for(int s=a;X[s]!='\0';s++){
	for(int j=k;Y[j]!='\0';j++){
	  if(X[s]==Y[j]){
	    count++;
	    k=j;
	    break;
	  }
	}
      }
      if(maxa[i]<count)maxa[i]=count;
    }
  }
  for(int i=0;i<n;i++){
    cout<<maxa[i]<<endl;
  }
  
  return 0;
}

C++: #define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

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

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