Go: package main

import (
	"fmt"
	"os"
	"strconv"
	"bufio"
	"strings"
	"sort"
)

// define
var (
	sc = bufio.NewScanner(os.Stdin)
)

func bordersInt(in_map [][]int, invalid int) [][]int{
	H, W := len(in_map), len(in_map[0])
	out_map := make([][]int, H+2)
	for h:=0; h<H+2; h++ {
		out_map[h] = make([]int, W+2)
		for w:=0; w<W+2; w++ {
			out_map[h][w] = invalid
		}
	}
	for h:=0; h<H; h++{
		for w:=0; w<W; w++{
			out_map[h+1][w+1] = in_map[h][w] 
		}
	}
	return out_map
}

func bordersString(in_map [][]string, invalid string) [][]string{
	H, W := len(in_map), len(in_map[0])
	out_map := make([][]string, H+2)
	for h:=0; h<H+2; h++ {
		out_map[h] = make([]string, W+2)
		for w:=0; w<W+2; w++ {
			out_map[h][w] = invalid
		}
	}
	for h:=0; h<H; h++{
		for w:=0; w<W; w++{
			out_map[h+1][w+1] = in_map[h][w] 
		}
	}
	return out_map
}

func scanIntLine(len int) []int{
	arr := make([]int, len)
	for i:=0; i<len; i++{
		sc.Scan()
		tmp, err := strconv.Atoi(sc.Text())
		if err == nil{
			arr[i] = tmp
		}
	}
	return arr
}

func scanStringLine(len int) []string{
	arr := make([]string, len)
	for i:=0; i<len; i++{
		sc.Scan()
		arr[i] = sc.Text()
	}
	return arr
}

func scanIntSplit(len int) []int{
	arr := make([]int, len)
	sc.Scan()
	for i, v := range strings.Split(sc.Text(), " "){
		tmp, err := strconv.Atoi(v)
		if err == nil{
			arr[i] = tmp
		}
	}
	return arr
}

func maxInt(args... int) int{
	sort.Ints(args)
	return args[len(args)-1]
}

func main(){
	buf := make([]byte, 0)
    sc.Buffer(buf, 1000000009)
	var n int 
	fmt.Scan(&n)
	dp := make([][]int, 1003)
	for i:=0; i<1003; i++ {
		dp[i] = make([]int, 1003)
	}
	input_lines := scanStringLine(2*n)
	for i:=0; i<n; i++ {
		S, T := input_lines[2*i], input_lines[2*i+1]
		lenS, lenT := len(S), len(T)
		for i:=1; i<lenS+1; i++ {
			for j:=1; j<lenT+1; j++ {
				if S[i-1] == T[j-1] {
					dp[i][j] = maxInt(dp[i-1][j-1]+1, dp[i-1][j], dp[i][j-1])
				} else {
					dp[i][j] = maxInt(dp[i-1][j], dp[i][j-1])
				}
			}
		}
		fmt.Println(dp[lenS][lenT])
	}
}

C++: #include <bits/stdc++.h>
#define ALL(a)  (a).begin(),(a).end()
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
using namespace std;
typedef long long ll;
typedef pair<int, int> P;
typedef pair<long long, long long> Pll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<long long> vll;
typedef vector<vector<long long>> vvll;
template <typename T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template <typename T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
const long long INF = 1LL << 60;

int main(){
int q;
cin >> q;
vi result(0);
while(q > 0){
  string s, t;
  cin >> s >> t;
  int ssize = s.size(), tsize = t.size();
  vvi dp(1100, vi(1100, 0));

  for(int i = 0; i < ssize; i++){
    for(int j = 0; j < tsize; j++){
      if(s.at(i) == t.at(j)) dp.at(i+1).at(j+1) = dp.at(i).at(j) + 1;
      else{
        chmax(dp.at(i+1).at(j+1), dp.at(i).at(j+1));
        chmax(dp.at(i+1).at(j+1), dp.at(i+1).at(j));
      }
    }
  }

  result.push_back(dp.at(ssize).at(tsize));

  q--;
}

for(auto x: result) cout << x << endl;
  
}

C++: 
#include<iostream>

int main(){
  int n;
  std::string x,y;
  std::cin>>n;
  int a[1000][1000];
  int b[n];

  for(int i=0;i<n;i++){
    std::cin>>x;
    std::cin>>y;
    for(int j=0;j<1000;j++){
      for(int k=0;k<1000;k++){
	a[j][k]=0;
      }
    }
    for(int j=0;j<=x.size();j++){
      for(int k=0;k<=y.size();k++){
	if(x[j]==y[k]){
	  a[j+1][k+0]=a[j][k]+1;
	}else{
	  if(a[j][k+1]>a[j+1][k]){
	    a[j+1][k+1]=a[j][k+1];
	  }else{
	    a[j+1][k+1]=a[j+1][k];
	  }
	}
      }
    }
    b[i]=a[x.size()][y.size()];
  }

  for(int i=0;i<n;i++){
  std::cout<<b[i]<<"\n";
  }

  return 0;
}

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

using namespace std;

int main(){
  int n;
  int k;
  int count;
  int max;
  cin>>n;
  char X[1001];
  char Y[1001];
  for(int i=0;i<n;i++){
    cin>>X;
    cin>>Y;
    k=0;
    max=0;
    for(int a=0;X[a]!='\0';a++){
    count=0;
      for(int i=a;X[i]!='\0';i++){
	for(int j=k;Y[j]!='\0';j++){
	  if(X[i]==Y[j]){
	    count++;
	    k=j;
	    break;
	  }
	}
      }
      if(max<count)max=count;
    }
    cout<<max<<endl;
    
  }
  return 0;
}

C++: #include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<map>
#include<set>
#include<cstdio>
#include<cmath>
#include<deque>
#include<numeric>
#include<queue>
#include<stack>
#include<cstring>
#include<limits>
#include<functional>
#include<unordered_set>
#include<iomanip>
#include<cassert>
#include<regex>
#include<bitset>
#include<complex>
#include<chrono>
#include<random>
#define rep(i,a) for(int i=(int)0;i<(int)a;++i)
#define rrep(i,a) for(int i=(int)a-1;i>=0;--i)
#define REP(i,a,b) for(int i=(int)a;i<(int)b;++i)
#define RREP(i,a,b) for(int i=(int)a-1;i>=b;--i)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(),x.end()
using ll=long long;
constexpr ll mod = 1e9 + 7;
constexpr ll INF = 1LL << 60;

ll gcd(ll n, ll m) {
	ll tmp;
	while (m!=0) {
		tmp = n % m;
		n = m;
		m = tmp;
	}
	return n;
}

ll lcm(ll n, ll m) {
	return abs(n) / gcd(n, m)*abs(m);//gl=xy
}
 
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
 
using namespace std;

int LCS(string s,string t){
  int n=s.size(),m=t.size();
  vector<vector<int>>dp(n+1,vector<int>(m+1));
  for(int i=0;i<n;++i){
    for(int j=0;j<m;++j){
      if(s[i]==t[j])dp[i+1][j+1]=dp[i][j]+1;
      else dp[i+1][j+1]=max(dp[i][j+1],dp[i+1][j]);
    }
  }
  return dp[n][m];
}


void solve(){
  int t;
  cin>>t;
  while(t--){
    string s,t;
    cin>>s>>t;
    cout<<LCS(s,t)<<"\n";
  }
}

int main(){
	ios::sync_with_stdio(false);
  cin.tie(0);
	cout<<fixed<<setprecision(15);
  solve();
	return 0;
}

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

using namespace std;

int dp[1501][1501];

int LCS(string x, string y){
  memset(dp, 0, sizeof(dp));
  if(x[0] == y[0])dp[0][0] = 1;
  for(int i=1;i<x.length();i++){
    dp[i][0] = dp[i-1][0];
    if(x[i] == y[0])dp[i][0] = 1;
  }
  for(int i=1;i<y.length();i++){
    dp[0][i] = dp[0][i-1];
    if(y[i] == x[0])dp[0][i] = 1;
  }
  for(int i=1;i<x.length();i++){
    for(int j=1;j<y.length();j++){
      if(x[i] == y[j])dp[i][j] = dp[i-1][j-1] + 1;
      else dp[i][j] = max(dp[i-1][j], dp[i][j-1]);
    }
  }
  return dp[x.length()-1][y.length()-1];
}

int main(){
  int q;cin >> q;
  for(int i=0;i<q;i++){
    string x, y;
    cin >> x >> y;
    cout << LCS(x, y) << endl;
  }
}

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

static const N = 100;

int main(){
	int n, p[N+1], m[N+1][N+1];
	cin >> n;
	for (int i=1; i<=n; i++){
		cin >> p[i-1] >> p[i];
	}

	for (int i=1; i<=n; i++) m[i][i] = 0;
	for (int l=2; l <= n; l++){
		for (int i=1; i<=n-l+1; i++){
			int j = i + l - 1;
			m[i][j] = 1 << 21;
			for (int k = i; k<= j - 1; k++){
				m[i][j] = min(m[i][j], m[i][k]+m[k+1][j]+p[i-1]*p[k]*p[j]);
			}
		}
	}

	cout << m[1][n] << endl;

	return 0;
}