Go: package main

import "fmt"

func main() {
	var n int
	fmt.Scan(&n)

	for q := 0; q < n; q++ {
		var s1, s2 string
		fmt.Scan(&s1, &s2)
		s1, s2 = " " + s1, " " + s2

		dp := make([][]int, len(s1))
		for i := range dp {
			dp[i] = make([]int, len(s2))
		}

		max := 0

		for i := 1; i < len(s1); i++ {
			for j := 1; j < len(s2); 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])
				}
				max = Max(max, dp[i][j])
			}
		}

		fmt.Println(max)
	}
}

func Max(n ...int) int {
	max := n[0]
	for _, v := range n[1:] {
		if v > max {
			max = v
		}
	}
	return max
}

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <functional>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <bitset>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
using namespace std;
typedef long long ll;
typedef pair<int,int> pint;
typedef vector<int> vint;
typedef vector<pint> vpint;
#define mp make_pair
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
int dx[4] = {1, 0, 0, -1};
int dy[4] = {0, 1, -1, 0};

int slove(string X, string Y){
	int dp[1000][1000];//dp[X?????????][Y?????????] = LCS
	int sizex = X.size();
	int sizey = Y.size();

	//???????????????????????????????????????????????????0????????????????????\?????????
	X = ' ' + X;
	Y = ' ' + Y;

	reps(i, 1, sizex + 1) dp[i][0] = 0;//?????????????????????0??????dp???0
	reps(i, 1, sizey + 1) dp[0][i] = 0;//?????????????????????0??????dp???0

	int ans = 0;//????°??????????
	reps(i, 1, sizex + 1){
		reps(j, 1, sizey + 1){
			if(X[i] == Y[j]) dp[i][j] = dp[i - 1][j - 1] + 1;
			else if(X[i] != Y[j]) dp[i][j] = max(dp[i][j - 1], dp[i - 1][j]);

			ans = max(ans, dp[i][j]);
		}
	}
	return ans;
}

int main(void){
	int n; cin >> n;
	string s1, s2;
	rep(i, n){
		cin >> s1 >> s2;
		printf("%d\n", slove(s1, s2));
	}
	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<=n; i++) c[i][0] = 0;
	for (int j=0; j<=m; j++) c[0][j] = 0;

	for (int i = 1; i <= n; i++){
		for (int j = 1; j <= m; 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(){
	string s1, s2;
	int q;
	cin >> q;
	for (int i=0; i<q;i++){
		cin >> s1 >> s2;
		cout << lcs(s1, s2) << endl;
	}
	return 0;

}

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

int LCS(string a,string b){
    int n1=a.size(),n2=b.size();
    int DP[n1+1][n2+1];
    DP[0][0]=0;
    rep(i,n1)DP[i+1][0]=0;
    rep(i,n2)DP[0][i+1]=0;
    rep(i,n1){
        rep(j,n2){
            if(a[i]==b[j])DP[i+1][j+1]=1+DP[i][j];
            else DP[i+1][j+1]=max(DP[i][j+1],DP[i+1][j]);
        }
    }
    return DP[n1][n2];
}

int main(){
    int q;cin>>q;
    string s,t;
    rep(i,q){
        cin>>s>>t;
        int ans=LCS(s,t);
        printf("%d\n",ans);
    }
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cassert>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) FOR(i,0,n)
#define rep(i,n) FOR(i,0,n)
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define vint vector<int>
#define vdouble vector<double>
#define vstring vector<string>
using namespace std;

#include<map>
#include<set>
#include<queue>

typedef long long ll;
typedef unsigned long long ull;

const int MAX_N = 1000000;
const int MAX_L = 1000;
int q;
string data[MAX_N][2];
ll mem[MAX_L][MAX_L];

ll eval(string s1, string s2, int i, int j){
	int ii = i - 1;
	int jj = j - 1;
	if (ii == -1 || jj == -1) return 0;
	if (s1[ii] == s2[jj]) return mem[i - 1][j - 1] + 1;
	if (s1[ii] != s2[jj]) return max(mem[i - 1][j], mem[i][j - 1]);
	throw "exception";
}

ll solve(string s1, string s2){

	int L1 = s1.size();
	int L2 = s2.size();
	rep(i, L1 + 1){
		rep(j, L2 + 1)
		{
			mem[i][j] = eval(s1, s2, i, j);
		}
	}

	return mem[L1][L2];
}

int main() {

	cin >> q;
	rep(i, q){
		cin >> data[i][0];
		cin >> data[i][1];
	}

	rep(i, q){
		cout << solve(data[i][0], data[i][1]) << endl;
	}
}

C++: #include <vector>
#include <iostream>
#include <algorithm>
#include <functional>
#include <string>
#include <limits.h>
#include <cmath>
#include <queue>
#include <map>
#include <iomanip>
#include <random>
#include <fstream>
#include <cassert>
#define rep(i, n) for (int i = 0; i < n; i++)
#define PI 3.14159265358979323846
#define MOD 1000000007
#define vi vector<int>
using namespace std;
using ll = long long;

// ----ここから下は以前競プロをやっていた時に使っていたものです----　

const int MAX = 1000000;

ll fac[MAX], finv[MAX], inv[MAX];

// テーブルを作る前処理
void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < MAX; i++){
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}

// 二項係数計算
long long COM(int n, int k){
  if (n < k) return 0;
  if (n < 0 || k < 0) return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

ll gcd(ll a, ll b)
{
  ll r;
  while ((r = a % b))
  {
    a = b;
    b = r;
  }
  return b;
}

template <class T> struct cord{
  T x,y;
};

template <class T> double dist(cord<T> a, cord<T> b){
  T dx=a.x-b.x;
  T dy=a.y-b.y;
  return sqrt(dx*dx+dy*dy);
}

struct s{
  int p,i,r;
};

//比較関数（降順）
bool cmpP(const s &a, const s &b){
  return a.p > b.p;
}

//比較関数（昇順）
bool cmpI(const s &a, const s &b){
  return a.i < b.i;
}

// ----本問について----
// 問題：最長共通部分列
// 問題文URL：https://onlinejudge.u-aizu.ac.jp/problems/ALDS1_10_C
// 所要時間：30分
// 学んだこと：自分のやってることがDPなのかメモ化再帰（？）なのかよくわからない
// ------------------

// ----ここから本問のソースコード----

// グローバル変数（入力）
ll q, L[1010][1010];
string X,Y;

ll solve(ll i, ll j) {
  if (L[i][j] != -1){return L[i][j];}

  if (i == 0 || j == 0){L[i][j]=0;}
  else if (X[i-1]==Y[j-1]){L[i][j]=solve(i-1,j-1)+1;}
  else {L[i][j]=max(solve(i-1, j), solve(i, j-1));}

  return L[i][j];
}

int main()
{
  //cout << fixed << setprecision(10);
  cin >> q;
  rep(ii,q){
    cin >> X;
    cin >> Y;
    ll x=X.size();
    ll y=Y.size();
    rep(i, 1010){
      rep(j, 1010){
        L[i][j]=-1;
      }
    }
    cout << solve(x, y) << endl;
  }

  return 0;
}

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

int LCS(string a, string b)
{
    int ret;
    int i, j;
    int len1, len2;
    int result[1001][1001] = {0};

    len1 = a.length();
    len2 = b.length();

    for (i = 1; i < len1; i++) {
        for (j = 1; j < len2; j++) {
            if (a[i] == b[j]) {
                result[i][j] = result[i - 1][j - 1] + 1;
            }
            else {
                result[i][j] = max(result[i][j - 1], result[i - 1][j]);
            }
        }
    }

    return result[len1 - 1][len2 - 1];
}

int main(void)
{
    int i;
    int num;
    int ret;
    string a, b;

    scanf("%d", &num);
    for (i = 0; i < num; i++) {
        cin >> a;
        cin >> b;
        ret = LCS(a, b);
        printf("%d\n", ret);
    }

    return 0;
}