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 INF=-10000;

  int d;
  int i,j,k;
  cin>>d;
  vector<int> ans(d);
  for(k=0;k<d;k++){
    string a,b;
    cin>>a>>b;

    vector<vector<int>> dp(a.size()+1,vector<int>(b.size()+1,0));
    dp.at(0).at(0)=0;
    for(i=0;i<a.size();i++){
      // cout<<"i "<<i<<endl;
      for(j=0;j<b.size();j++){
        // cout<<"j "<<j<<endl;
        if(a.at(i)==b.at(j)){
          dp.at(i+1).at(j+1)=dp.at(i).at(j)+1;
        } else{
          dp.at(i+1).at(j+1)=max(dp.at(i).at(j+1),dp.at(i+1).at(j));
        }
      }
    }

    ans.at(k)=dp.at(a.size()).at(b.size());
}

for(k=0;k<d;k++)
cout<<ans.at(k)<<endl;

}

C++: #include<iostream>
#include<algorithm>
using namespace std;
int dp[1001][1001];
string s,t;
int n,m,a,ans;
int main(){
  cin>>a;
  for(int b=0;b<a;b++){
    cin>>s>>t;
    for(int i=0;i<=1000;i++)
      for(int j=0;j<=1000;j++)
	dp[i][j]=0;
    m=s.size();
    n=t.size();
    ans=0;
    for(int i=1;i<=m;i++){
      for(int j=1;j<=n;j++){
	if(s[i-1]==t[j-1]){
	  dp[i][j]=dp[i-1][j-1]+1;
	}else{
	  dp[i][j]=max(dp[i-1][j],dp[i][j-1]);
	}
      }
    }  
    cout<<dp[m][n]<<endl;
  }
  return 0;
}

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

using namespace std;

int q;
int main() {
	cin >> q;
	for (int i = 0; i < q; i++) {
		string x, y;
		cin >> x >> y;
		int m = x.size();
		int n = y.size();
		x = ' ' + x;
		y = ' ' + y;
		int maxl = 0;
		int c[1001][1001];
		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][j - 1], c[i - 1][j]);
				}
				maxl = max(maxl, c[i][j]);
			}
		}
		cout << maxl << endl;
	}
	return 0;
}

C++: #include<iostream>
#include<cmath>
#include<algorithm>
#include<string>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<iomanip>
#include<bitset>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> P;
typedef pair<ll,P> P1;
typedef pair<P,P> P2;
#define pu push
#define pb push_back
#define mp make_pair
#define eps 1e-7
#define INF 1000000000
#define fi first
#define sc second
#define rep(i,x) for(ll i=0;i<x;i++)
#define repn(i,x) for(ll i=1;i<=x;i++)
#define SORT(x) sort(x.begin(),x.end())
#define ERASE(x) x.erase(unique(x.begin(),x.end()),x.end())
#define POSL(x,v) (lower_bound(x.begin(),x.end(),v)-x.begin())
#define POSU(x,v) (upper_bound(x.begin(),x.end(),v)-x.begin())

const int MAX = 510000;
const int MOD = 1000000007;

int main(){
  ll N; cin >> N;
  vector<string> v(2 * N);
  rep(i, 2 * N) cin >> v[i];
  rep(loop, N){
    string s,t;
    s = v[2 * loop]; t = v[2 * loop + 1];
    ll a = s.size(), b = t.size();
    vector<vector<ll> > dp(a + 1 , vector<ll>(b + 1, 0) );
    rep(i,a){
      rep(j,b){
        if(s[i] == t[j]){
          dp[i + 1][j + 1] = max(dp[i + 1][j] , max(dp[i][j + 1], dp[i][j] + 1) );
        }
        else{
          dp[i + 1][j + 1] = max(dp[i + 1][j] , dp[i][j + 1]);
        }
      }
    }
    /*
    rep(i,a + 1){
      rep(j,b + 1){
        cout << dp[i][j] << " ";
      }
      cout << endl;
    }
    */
    cout << dp[a][b] << 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], LMAX=0;;
  int m=X.size(), n=Y.size();

  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]);
      }
      LMAX=max(LMAX, c[i][j]);
    }
  }

  return LMAX;
}

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;
#define MAX 1000

int c[MAX + 1][MAX + 1];

int lcs(string x, string y) {
	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][j - 1], c[i - 1][j]);
			}
			maxl = max(maxl, c[i][j]);
		}
	}
	return maxl;
}

int main()
{
	int q;
	cin >> q;
	string x, y;
	int l[150] = { 0 };

	for (int i = 0; i < q; i++) {
		cin >> x >> y;
		l[i] = lcs(x, y);
	}
	for (int i = 0; i < q; i++) {
		cout << l[i] << endl;
	}
	return 0;
}

C++: #include<bits/stdc++.h>

using namespace std;

void printdpTable(vector<vector<int> > a){
    cout << "- dp table -" << endl;
    for(int i = 0; i < a.size(); i++){
        for(int j = 0; j < a[0].size(); j++){
            cout << a[i][j] << " ";
        }
        cout << endl;
    }
    cout << "- dp table -" << endl;
}

//すべての最長部分文字列をの長さ出力する
void printLcs(string x, string y){
    int n = x.length();
    int m = y.length();
    vector<vector<int> > a(n+1, vector<int>(m+1, 0));
    x = ' ' + x;
    y = ' ' + y;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            if(x[i] == y[j]){
                a[i][j] = a[i-1][j-1]+1;
            }else{
                a[i][j] = max(a[i-1][j], a[i][j-1]);
            }
        }
    }
    cout << a[n][m] << endl;
}

int main(void){
    int n;
    cin >> n;
    string x, y;
    for(int i = 0; i < n; i++){
        cin >> x >> y;
        printLcs(x,y);
    }
    return 0;
}