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++: /*
    Problem 38
    https://onlinejudge.u-aizu.ac.jp/problems/ALDS1_10_C
*/
#include <bits/stdc++.h>
using namespace std;
/* typedef */
typedef long long ll;
typedef pair<int, int> pii;
/* constant */
const int INF = 1 << 30;
const ll LINF = 1LL << 50;
const int NIL = -1;
const int MAX = 1005;
const int mod = 1000000007;
const double pi = 3.141592653589;
/* global variables */
vector<vector<int>> dp(MAX, vector<int>(MAX));
/* function */
void calc(string s, string t) {
    int S = s.size(), T = t.size();
    // init
    for (int i = 0; i < S; i++) for (int j = 0; j < T; j++) dp[i][j] = 0;
    for (int i = 0; i < S; i++) {
        for (int j = 0; j < T; j++) {
            dp[i+1][j+1] = max(dp[i+1][j], dp[i][j+1]);
            if (s[i] == t[j]) dp[i+1][j+1] = dp[i][j] + 1;
        }
    }
    cout << dp[S][T] << '\n';
}
/* main */
int main(){
    int n;
    cin >> n;
    string s, t;
    for (int i = 0; i < n; i++) {
        cin >> s >> t;
        calc(s, t);
    }
}

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=0;i<n;i++){
        for(int j=0;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 max
}
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 <cstdio>
#include <cstring>
#include <sstream>
#include <algorithm>
#include <math.h>
#include <map>
#include <functional>
#include <iomanip>
#include <vector>
#include <queue>
#include <stack>
#include <set>
#include <typeinfo>
#define PI 3.14159265359
#define INF 99999999;
#define rep(i, n) for(int i=0; i<n; i++)
#define REP(n) rep(i, n)
#define EPS 1e-10
typedef long long ll;
using namespace std;
typedef pair<int, int> P;

double distanceAB(double xa, double ya, double xb, double yb);
void trace(int A[], int N);

/*
class Target
{
public:
	vector <string> draw(int n)
	{

	}
};
*/


static const int N = 1000;
int c[N + 1][N + 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=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;
	REP(n)
	{
		cin >> s1 >> s2;
		cout << lcs(s1, s2) << endl;
	}
	
	return 0;
}


void trace(int A[], int N)
{
	REP(N)
	{
		if (i > 0) cout << " ";
		cout << A[i];
	}
	cout << endl;
}


double distanceAB(double xa, double ya, double xb, double yb)
{
	return sqrt((xb-xa)*(xb-xa) + (yb-ya)*(yb-ya));
}

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

int dp[1010][1010];

int main() {
	int q;
	cin >> q;
	vector<string> x(q), y(q);
	for (int i = 0;i < q;i++) {
		cin >> x[i] >> y[i];
	}

	for (int i = 0;i <= 1000;i++) {
		dp[i][0] = 0;
		dp[0][i] = 0;
	}
	for (int i = 0;i < q;i++) {
		for (int j = 1;j <= x[i].size();j++) {
			for (int k = 1;k <= y[i].size();k++) {
				dp[j][k] = max(dp[j - 1][k], dp[j][k - 1]);
				if (x[i][j] == y[i][k]) {
					dp[j][k] = max(dp[j][k], dp[j - 1][k - 1] + 1);
				}
			}
		}
		cout << dp[x[i].size()][y[i].size()] << endl;
	}

	return 0;
}

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

using namespace std;
static const int N = 100;

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;
	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]);
		}
	}
	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);
		cout << endl;
	}
	return 0;
}

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

using namespace std;
int main(){
  int dataset, i, j, k, alen, blen;
  string a, b;
  cin >> dataset;
  for (i = 0; i < dataset; ++i){
    cin >> a >> b;
    alen = a.length();
    blen = b.length();
    int lcs[alen+1][blen+1];
    for (j = 0; j <= alen; ++j){
      for (k = 0; k <= blen; ++k){
        lcs[j][k] = 0;
      }
    }
    for (j = 1; j <= alen; ++j){
      for (k = 1; k <= blen; ++k){
        if(a.at(j-1) == b.at(k-1)){
          lcs[j][k] = lcs[j-1][k-1] + 1;
        }else{
          lcs[j][k] = max(lcs[j-1][k], lcs[j][k-1]);
        }
      }
    }
    cout << lcs[alen][blen] << endl;
  }
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  int q;
  cin>>q;
  string a,b;
  int x[1001][1001];
  x[0][0]=0;
  for(int i=1;i<=1000;i++){
    x[0][i]=0;
    x[i][0]=0;
  }
  for(int i=0;i<q;i++){
    cin>>a>>b;
    for(int j=1;j<=b.size();j++){
      for(int l=1;l<=a.size();l++){
	if(a[l-1]==b[j-1]){
	  if(x[j-1][l-1]+1>x[j][l-1]){
	    x[j][l]=x[j-1][l-1]+1;
	  }else{
	    x[j][l]=x[j][l-1];
	  }
	}else{
	  if(x[j-1][l]>x[j][l-1]){
	    x[j][l]=x[j-1][l];
	  }else{
	    x[j][l]=x[j][l-1];
	  }
	}
      }
    }
    cout<<x[b.size()][a.size()]<<endl;
  }
  return(0);
}