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 lcs(const string& a, const string& b) {
    int dp[1000+1][1000+1];
    int al = a.size();
    int bl = b.size();
    memset(dp, 0, sizeof(dp[0][0])*al*bl);
    for (int i = 1; i <= al; ++i) {
        for (int j = 1; j <= bl; ++j) {
            if(a[i - 1] == b[j - 1]) {
//                cout << "=" << endl;
                dp[i][j] = dp[i - 1][j - 1] + 1;
            } else {
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
            }
            // cout << a[i] << ":" << b[j] << endl;
            // cout << i << "," << j << "," << dp[i][j] << endl;
            // cout << endl;
        }
    }
    return dp[al][bl];
}

int main() {
    int n;
    scanf("%d", &n);

    for (int i = 0; i < n; ++i) {
        string a, b;
        cin >> a >> b;
        cout << lcs(a, b) << endl;
    }
}

C++: #include <bits/stdc++.h>
#define ll long long
#define ld long double
#define fi first
#define se second
#define pb push_back
#define pii pair<int,int>
#define pll pair<long long,long long>
#define all(v) v.begin(), v.end()
using namespace std;

string a,b;
int dp[1010][1010];
bool u[1010][1010];

int fn(int i,int j){
    if( i < 0 || j < 0 ) return 0;
    if( u[i][j] ) return dp[i][j];
    u[i][j] = true;
    int ans = max( fn(i-1,j) , fn(i,j-1) );
    if( a[i]==b[j] ) ans = max( ans , 1+fn(i-1,j-1) );
    return dp[i][j] = ans;
}

int main()
{

    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int t;
    cin >> t;
    for(int i=1; i<=t; i++){
        cin >> a >> b;
        for(int j=0; j<a.size(); j++) for(int k=0; k<b.size(); k++) u[j][k] = false;
        cout << fn( a.size()-1 , b.size()-1 ) << "\n";
    }

    return 0;
}

C++: #include <bits/stdc++.h>
#define REP0(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define REPB0(i,n) for(int i=n-1;i>=0;i--)
#define REPB1(i,n) for(int i=n;i>0;i--)
#define llong long long
#define INF 2000000000
#define NIL -1
#define N 1000
using namespace std;
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;
  REP1(i,m) C[i][0]=0;
  REP1(i,n) C[0][i]=0;
  REP1(i,m){
    REP1(j,n){
      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;
  scanf("%d",&n);
  REP0(i,n){
    cin>>s1>>s2;
    printf("%d\n",LCS(s1,s2));
  }
  return 0;
}

C++: #include <bits/stdc++.h>
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;
    for(int i=0;i<n+1;i++) c[0][i]=0;
    for(int i=0;i<m+1;i++) c[i][0]=0;
    for(int i=1;i<m+1;i++){
        for(int j=1;j<n+1;j++){
            if(X[i-1]==Y[j-1]) 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(void){
    int q;
    string X,Y;
    cin >> q;
    for(int i=0;i<q;i++){
        cin >> X >> Y;
        cout << lcs(X,Y) << endl;
    }
}

C++: #include<iostream>
#include<vector>
#include<limits.h>
#include<string>
using namespace std;
 
int LCS(string a, string b){
    int m=a.size();
    int n=b.size();
    int T[m+1][n+1];
    int i,j;
    for (i=0;i<m+1;i++) T[i][0]=i;
    for (j=0;j<n+1;j++) T[0][j]=j;
    for (i=1;i<m+1;i++){
        for (j=1;j<n+1;j++){
            int min=T[i-1][j]+1;
            if (min>T[i][j-1]+1){
                min=T[i][j-1]+1;
            }
            if ((a[i-1]==b[j-1])&&(min>T[i-1][j-1]+1)){
                min=T[i-1][j-1]+1;
            }
            T[i][j]=min;
        }
    }
    return m+n-T[m][n];
}
 
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int m,i;
    cin >> m;
     
    string a,b;
    for (i=0;i<m;i++){
        cin >> a >> b;
        cout << LCS(a,b) << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
#include <string>
#include <cstring>
#include <cctype>
#include <cmath>
#include <stack>
#include <queue>
#include <vector>
#include <set>
#include <map>
#include <list>
#include <stdio.h>
#include <string.h>
#include <cstdlib>
#include <math.h>
#include <bitset>
#include <iterator>
#include <iomanip>
#include <sstream>
#define INF 2000000000
using namespace std;
int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1};
#define sym cout<<"---------"<<endl;
#define ll long long
#define PL pair<long long, long long>
#define P pair<int,int>
#define mk make_pair
#define en endl
#define WHITE 0
#define BLACK 2
#define GRAY 1
#define RE return 0
#define int ll
//
//vector<int> G[20];
//
//// 巡回セールスマン問題
//
//signed main(){
//  int v,e;
//  cin>>v>>e;
//
//  for(int i=0; i<e; i++){
//    int a,b;
//    cin>>a>>b;
//    G[a].push_back(b);
//  }
//}























////  最長共通部分列

int dp[1005][1005];

signed main(){
  int n;
  cin>>n;
  for(int i=0; i<n; i++){
    string s1,s2;
    cin>>s1>>s2;
    s1=" "+s1;
    s2=" "+s2;
    int maxl=0;
    for(int i=0; i<=s1.size()-1; i++) for(int j=0; j<=s2.size(); j++) dp[i][j]=0;
    for(int i=1; i<=s1.size()-1; i++){
      for(int j=1; j<=s2.size(); 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]);
        maxl=max(maxl,dp[i][j]);
      }
    }
    cout<<maxl<<en;
  }
}

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

static const int N = 1000;

int max(int a, int b)
{
	if(a > b)
		return a;
	else 
		return b;
}
int lcs(string X, string Y)
{
	int c[N+1][N+1] = {0};
	int m = X.size();
	int n = Y.size();

	int max1 = 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] = max(c[i-1][j],c[i][j-1]);
			}
			max1 = max(max1,c[i][j]);
		}
	}

	return max1;
}
int main()
{
	string a,b;
	int n;
	scanf("%d", &n);
	for(int i=0; i<n; i++)
	{
		cin >> a >> b;
		printf("%d\n",lcs(a,b));
	}

	return 0;
}