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 <stdio.h>
#include <algorithm>
#define MAX 1000


int lcs(std::string X, std::string Y) {
    int c[MAX+1][MAX+1];
    int maxl = 0;
    int m = X.size();
    int n = Y.size();
    for (int i = 1; i <= m; i++) {
        c[i][0] = 0;
    }
    for (int i = 1; i <= n; i++) {
        c[0][i] = 0;
    }
    X = ' ' + X;
    Y = ' ' + Y;
    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] = std::max(c[i-1][j], c[i][j-1]);
            }
            maxl = std::max(maxl, c[i][j]);
        }
    }
    return maxl;
}

int main() {
    std::string s1, s2;
    int n;
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        std::cin >> s1 >> s2;
        
        printf("%d\n", lcs(s1, s2));
    }
    
    return 0;
}

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

int get_lcs_length(std::string X, std::string Y) {
    int m = X.length();
    int n = Y.length();
    vector<vector<int>> c(m + 1, vector<int>(n + 1, 0));
    X = " " + X;
    Y = " " + Y;

    int max_length = 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] = std::max(c[i - 1][j], c[i][j - 1]);
            }
            max_length = std::max(max_length, c[i][j]);
        }
    }
    return max_length;
}

int main() {
    int q;
    std::cin >> q;
    for (int i = 0; i < q; i ++) {
        std::string X, Y;
        std::cin >> X;
        std::cin >> Y;
        std::cout << get_lcs_length(X, Y) << std::endl;
    }

}

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

using namespace std;

const int N=1010;

int dp[N][N];

int main()
{
    int n;

    char s1[N],s2[N];

    cin>>n;

    while(n--)
    {
        cin>>(s1+1)>>(s2+1);

        int len1=strlen(s1+1),len2=strlen(s2+1);
        for(int i=1;i<=len1;i++)
        {
            for(int j=1;j<=len2;j++)
            {
                if(s1[i]==s2[j])
                {
                    dp[i][j]=dp[i-1][j-1]+1;
                }else
                {
                    dp[i][j]=max(dp[i-1][j],dp[i][j-1]);
                }
            }
        }

        cout<<dp[len1][len2]<<endl;
    }

    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>

using namespace std;

int q;
char X[1000], Y[1000];
int dp[1001][1001];

int main(void) {

    scanf("%d", &q);

    for (int i = 0; i < q; ++i) {
        scanf("%s %s", X, Y);
        int xlen = strlen(X), ylen = strlen(Y);
        for (int x = 0; x < xlen; ++x) {
            for (int y = 0; y < ylen; ++y) {
                if (X[x] == Y[y]) {
                    dp[x + 1][y + 1] = dp[x][y] + 1;
                }
                else {
                    if (dp[x + 1][y] > dp[x][y + 1]) {
                        dp[x + 1][y + 1] = dp[x + 1][y];
                    }
                    else {
                        dp[x + 1][y + 1] = dp[x][y + 1];
                    }
                }
            }
        }
        printf("%d\n", dp[xlen][ylen]);
        memset(dp, 0, sizeof(int)*1001*1001);
    }

    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(obj) (obj).begin(),(obj).end()

int solve(string ss,string tt){
  int c[1001][1001];
  int m=ss.size();
  int n=tt.size();
  int k=0;
  ss=' '+ss;
  tt=' '+tt;
  for(int i=0;i<=m;i++)c[0][i]=0;
  for(int i=0;i<=n;i++)c[i][0]=0;
  for(int i=1;i<=m;i++){
    for(int j=1;j<=n;j++){
      if(ss[i]==tt[j]){
        c[i][j]=c[i-1][j-1]+1;
      }
      else{
        c[i][j]=max(c[i][j-1],c[i-1][j]);
      }
      k=max(k,c[i][j]);
    }
  }
  return k;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    string ss,tt;
    cin>>n;
    rep(i,n){
      cin>>ss>>tt;
      cout<<solve(ss,tt)<<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 = 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++: /*
 * ALDS1_10_C.cpp
 *
 *  Created on: May 5, 2018
 *      Author: 13743
 */

#include<cstdio>
#include<cstring>
#include<algorithm>

//int dp[1001][1001];

int lcm(char* X, char* Y, int nx, int ny) {
int dp[1001][1001];
	dp[1][1] = (X[0] == Y[0]);
	for(int i=1; i<=nx; i++) {
		for(int j=1; j<=ny; j++) {
			dp[i][j] = (X[i-1]==Y[j-1]) + dp[i-1][j-1];
			dp[i][j] = std::max(dp[i-1][j], dp[i][j]);
			dp[i][j] = std::max(dp[i][j-1], dp[i][j]);
		}
	}
	return dp[nx][ny];
}

int main() {
	int q;
	scanf("%d", &q);
	char X[1001];
	char Y[1001];
	while(q--) {
		scanf("%s", X);
		scanf("%s", Y);
		int nx = (int)strlen(X);
		int ny = (int)strlen(Y);
		printf("%d\n", lcm(X, Y, nx, ny));
	}
}