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 <string>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <map>
#include <set>
#include <queue>
#include <list>
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,a,b) for(int i=int(a);i<int(b);++i)
#define crep(i) for(char i='a';i<='z';i++)
#define psortsecond(A,N) sort(A,A+N,[](const pii &a, const pii &b){return a.second<b.second;});
#define psortfirst(A,N) sort(A,A+N,[](const pii &a, const pii &b){return a.first<b.first;});
#define All(x) (x).begin(),(x).end()
int ctoi(const char c){
  if('0' <= c && c <= '9') return (c-'0');
  return -1;
}
using namespace std;
using pii  = pair<int,int>;
long long gcd(long long a, long long b){return (b == 0 ? a : gcd(b, a%b));}
long long lcm(long long a, long long b){return a*b/gcd(a,b);}
typedef long long ll;
#define MOD 1000000007
#define EPS 10e-8

string A,B;

ll dp[1007][1007];

int LCS(string A,string B){
    REP(i,1,A.size()+1){
        REP(j,1,B.size()+1){
            if(A[i-1]==B[j-1]){
                dp[i][j]=dp[i-1][j-1]+1;
            }
            else{
                dp[i][j]=max(dp[i-1][j],dp[i][j-1]);
            }
        }
    }
    return dp[A.size()][B.size()];
}

int main(){
    ll N;cin>>N;
    rep(i,N){
        cin>>A>>B;
        cout << LCS(A,B) << endl;
    }
}

C++: #include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<algorithm>
#include<bitset>
#include<vector>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<iomanip>
#include <functional>
using namespace std;
typedef long long ll;
const int mod = 1000000007;
const int INF = 1 << 28;
//cout << fixed << std::setprecision(9)
//memset(a, 0, sizeof(a));
//--------------------------

int dp[1001][1001];

int lcs(string x, string y)
{	
	int n = x.size();
	int m = y.size();

	x = " " + x;
	y = " " + y;

	for (int i = 1; i <= n; i++) dp[i][0] = 0;
	for (int j = 1; j <= m; j++) dp[0][j] = 0;

	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= m; 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[n][m];
}

int main()
{
	int q;
	string s1, s2;
	cin >> q;

	for (int i = 0; i < q; i++) {		
		cin >> s1 >> s2;
		cout << lcs(s1, 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();
	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() {
		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;

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++) c[i][0] = 0;
  for (int i = 0; i < n; i++) c[0][i] = 0;

  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
        c[i][j] = max(c[i][j - 1], c[i - 1][j]);
    }
  }
  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 str1, string str2) {
	int n1 = str1.size();
	int n2 = str2.size();
	int A[n1 + 1][n2 + 1];
	for (int i = 1; i <= n1; i++) A[i][0] = 0;
	for (int j = 1; j <= n1; j++) A[0][j] = 0;

	for (int i = 1; i <= n1; i++) {
		for (int j = 1; j <= n2; j++) { 
			if (str1[i - 1] == str2[j - 1]) {
				A[i][j] = A[i - 1][j - 1] + 1; //?????´??????+1????????¨???????????¨???????????\??????i-1, j-1????????´??°???i,j?????????????????????+1????????¨???????????¨i-1,j??¨?????§?????????????????¶??????
			} else {
				A[i][j] = max(A[i - 1][j], A[i][j - 1]); //?????´?????????????????§i,j??????????????? i-1,j??¨i,j-1
			}
		}
	}
	return A[n1][n2];
}

int main() {
	int n;
	string str1, str2;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> str1 >> str2;
		cout << lcs(str1, str2) << 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();
	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() {
	
	string s1, s2;
	int n; cin >> n;
	for(int i = 0; i < n; i++){
		cin >> s1 >> s2;
		cout << lcs(s1, s2) << endl;
	}
	
	return 0;
}