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 <cstdio>
#include <vector>
using namespace std;

#define MAXX 1024

int min(int a, int b){
	return a > b ? b : a;
}
int max(int a, int b){
	return a < b ? b : a;
}

int LCS(char* a, char* b){
	int al = 0, bl = 0;
	for (int i = 0; i < MAXX; i++){
		if (a[i] == '\0') al = i;
		if (b[i] == '\0') bl = i;
		if (al != 0 && bl != 0) break;
	}
	vector< vector<int> > table(al, vector<int>(bl, 0));
	for (int i = 0; i < al + bl - 1; i++){
		for (int j = max(i - al + 1, 0); j <= min(bl - 1, i); j++){
			if (a[i - j] == b[j]){
				if (i - j == 0 || j == 0){
					table[i - j][j] = 1;
				}
				else{
					table[i - j][j] = table[i - j - 1][j - 1] + 1;
				}
			}
			else{
				if (i - j == 0 && j == 0){
					table[i - j][j] = 0;
				}
				else if (i - j == 0 && j != 0){
					table[i - j][j] = table[i - j][j - 1];
				}
				else if (i - j != 0 && j == 0){
					table[i - j][j] = table[i - j - 1][j];
				}
				else{
					table[i - j][j] = max(table[i - j - 1][j], table[i - j][j - 1]);
				}
			}
		}
	}
	return table[al-1][bl-1];
}

int main(){
	int n, dum;
	scanf("%d", &n);
	char a[MAXX], b[MAXX];
	for (int i = 0; i < n; i++){
		scanf("%s", &a);
		scanf("%s", &b);
		printf("%d\n", LCS(a, b));
	}

	return 0;
}

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

int lcs(string str1, string str2){
  int C[1001][1001];
  int max = 0;

  str1 = ' ' + str1;
  str2 = ' ' + str2;

  for(int i = 1 ; i <= str1.size() ; i++) C[i][0] = 0;
  for(int j = 1 ; j <= str2.size() ; j++) C[0][j] = 0;

  for(int i = 1 ; i <= str1.size() ; i++){
    for(int j = 1 ; j <= str2.size() ; j++){
      if(str1[i] == str2[j]){
	C[i][j] = C[i - 1][j - 1] + 1;
      }else{
	if(C[i - 1][j] > C[i][j -1]) C[i][j] = C[i - 1][j];
	else if(C[i][j -1] > C[i - 1][j]) C[i][j] = C[i][j - 1];
      }

      if(max > C[i][j]) max = max;
      else if(C[i][j] > max) max = C[i][j];

    }
  }

  return max;
}

int main(){
  string str1, str2;
  int n;

  cin >> n;

  for(int i = 0 ; i < n ; i++){
    cin >> str1 >> str2;
    cout << lcs(str1, str2)-1 << endl;
  }

  return 0;
}

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

#define MAX 1000

int lcs(string X, string Y) {
    int c[MAX+1][MAX+1];
    int m = X.size();
    int n = Y.size();
    int i, j;
    int maxlen = 0;
    X = " " + X;
    Y = " " + Y;

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

    for(i = 1 ; i <= m ; i++ ) {
        for(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]);
            }
            maxlen = max(maxlen, c[i][j]);
        }
    }
    return maxlen;
}

int main (void) {
    int N, i;
    string x, y;

    cin >> N;

    for(i = 0 ; i < N ; i++) {
        cin >> x;
        cin >> y;
        printf("%d\n", lcs(x,y));
    }

    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;    // X[0]に空白を挿入
    Y = ' ' + Y;    // Y[0]に空白を挿入
    for (int i = 0; i <= m; i++) c[i][0] = 0;
    for (int j = 0; 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;
}