Go: package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}
	for i := 0; i < n; i++ {
		strX := nextText(sc)
		strY := nextText(sc)
		fmt.Println(calcLcs(strX, strY))
	}
}

func calcLcs(strX, strY string) int {
	lenX, lenY := len(strX), len(strY)
	memo := make([][]int, lenX+1)
	for i := 0; i < lenX+1; i++ {
		memo[i] = make([]int, lenY+1)
	}

	lcs := 0
	for i := 1; i < lenX+1; i++ {
		for j := 1; j < lenY+1; j++ {
			if strX[i-1] == strY[j-1] {
				memo[i][j] = memo[i-1][j-1] + 1
			} else {
				if memo[i-1][j] > memo[i][j-1] {
					memo[i][j] = memo[i-1][j]
				} else {
					memo[i][j] = memo[i][j-1]
				}
			}
			if memo[i][j] > lcs {
				lcs = memo[i][j]
			}
		}
	}
	return lcs
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

C++: #include <bits/stdc++.h>
using namespace std;
static const int hoge = 1000;
int C[1000][1000];
int lc(string F, string S){

    fill(C[0],C[hoge],0);
    int m = F.size(), n = S.size();
    int len=0;
    for(int i=0; i<m; i++){
        for (int j = 0; j < n; ++j) {
            if (F[i] == S[j]) {
                if (i - 1 >= 0 && j - 1 >= 0)
                    C[i][j] = C[i - 1][j - 1] + 1;
                else
                    C[i][j] = 1;
            } else if (i - 1 < 0) {
                if(j-1 < 0){
                    C[i][j] = 0;
                }else{
                    C[i][j] = C[i][j - 1];
                }
            }else if(j-1 < 0) {
                C[i][j] = C[i - 1][j];
            }else{
                C[i][j] = max(C[i-1][j], C[i][j - 1]);
            }
            len = max(len, C[i][j]);
        }
    }
    return len;
}

int main() {
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    string ar1,ar2;
    for (int i = 0; i < n; ++i) {
        cin >> ar1 >> ar2;
        cout << lc(ar1,ar2) << endl;
    }
    return 0;
}

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

using namespace std;

string  X,Y;
int q;

int do_dp(int ax,int ay){
  int dp[ax + 100][ay + 100] = {0};
  
  for(int i = 0;i < ax;i++){
    if(X[i] == Y[0]) dp[i][0] = 1;
    if(i > 0) dp[i][0] = max(dp[i][0],dp[i - 1][0]);
  }
  
  for(int j = 0;j < ay;j++){
    if(X[0] == Y[j]) dp[0][j] = 1;
    if(j > 0) dp[0][j] = max(dp[0][j],dp[0][j - 1]);
  }

  for(int i = 1;i < ax;i++){
    for(int j = 1;j < ay;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]);
      }
    }
  }
  
  /*for(int i = 0;i < ax;i++){
    for(int j = 0;j < ay;j++){
      cout << dp[i][j] << " ";
    }
    cout << '\n';
    }*/
  
  return dp[ax - 1][ay - 1];
}

int main(){
  string str;
  
  cin >> q;
  
  int A[q];
  
  for(int i = 0;i < q;i++){
    cin >> X;
    cin >> Y;
    //cout << X.size() << " " << Y.size() << '\n';
    A[i] = do_dp(X.size(),Y.size());
  }
  
  for(int i = 0;i < q;i++){
    cout << A[i] << '\n';
  }
  
  return 0;
}

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

using namespace std;

int lcs (string x, string y) {

    int m, n, c[1001][1001], i, j, maxl = 0;

    m = x.size();
    n = y.size();

    x = ' ' + x;
    y= ' ' + y;

    for (i = 0; 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 - 1] == y[j - 1]) {
                    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 () {

    int N, i;
    string x, y;

    cin >> N;

    for (i = 0; i < n; i++) {
        cin >> x >> y;
        cout << lcs (x, y) << endl;

    }

    return 0;

}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>
#define FOR(i,b,e) for(int i=b;i<e;i++)
#define REP(i,n) FOR(i,0,n)
using namespace std;

int dp[1001][1001];
string s1, s2;

int lcs(int n1, int n2) {
  if (dp[n1][n2] != -1) return dp[n1][n2];
  
  return dp[n1][n2] = max(lcs(n1 - 1, n2), lcs(n1, n2 - 1));
}

int main() {
	cin.tie(0);
 	ios::sync_with_stdio(false);

  REP(i, 1001) dp[i][0] = 0;
  REP(i, 1001) dp[0][i] = 0;

  int q; cin >> q;
  REP(i, q) {
    cin >> s1;
    cin >> s2;

    cout << lcs(s1.length(), s2.length()) << endl;
  }
}

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

#if __has_include("print.hpp")
  #include "print.hpp"
#endif

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

typedef long long ll;
typedef pair<int, int> p;

int n, w;
vector<vector<int>> dp(500, vector<int>(10500, -1));
vector<int> vv;
vector<int> wv;

void solve(){
  for (int i = n - 1; i >= 0; i--) {
    for (int j = 0; j < w; j++) {
      if(j < wv[i]){
        dp[i][j] = dp[i+1][j];
      }else{
        dp[i][j] = max(dp[i+1][j], dp[i+1][j-wv[i]] + vv[i]);
      }
    }
  }
}

int main(){
  cin >> n >> w;
  for (int i = 0; i < n; i++)
  {
    int tmp1, tmp2;
    cin >> tmp1 >> tmp2;
    wv.push_back(tmp1);
    vv.push_back(tmp2);
  }

  solve();
  cout << dp[0][w] << endl;
}

C++: 
#include<iostream>
#include<algorithm>
#include<string>
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 = 1; 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++) {
			cout << c[i][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() {
	int n;
	string x, y;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> x >> y;

		cout << lcs(x, y) << endl;
	}

	
}