Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)
	for i := 0; i < n; i++ {
		x := getNextString(scanner)
		y := getNextString(scanner)

		fmt.Fprintln(writer, lcs(x, y))
	}

	writer.Flush()
}

func lcs(x, y string) int {
	lx := len(x)
	ly := len(y)
	dp := make([][]int, lx+1)
	for i := 0; i <= lx; i++ {
		dp[i] = make([]int, ly+1)
	}
	for i := 0; i < lx; i++ {
		for ii := 0; ii < ly; ii++ {
			if x[i] == y[ii] {
				dp[i+1][ii+1] = dp[i][ii] + 1
				continue
			}
			dp[i+1][ii+1] = dp[i][ii+1]
			if dp[i+1][ii] > dp[i+1][ii+1] {
				dp[i+1][ii+1] = dp[i+1][ii]
			}
		}
	}
	return dp[lx][ly]
}

C++: #include<cstdio>
#include<vector>
#include<algorithm>
#include<utility>
#include<numeric>
#include<iostream>
#include<array>
#include<string>
#include<sstream>
#include<stack>
#include<queue>
#include<list>
#define _USE_MATH_DEFINES

#include<math.h>
#include<map>

#define SENTINEL 1000000001

#define min(a,b) (a)>(b)?(b):(a)
#define max(a,b) (a)>(b)?(a):(b)

using namespace std;

int LCS[1000][1000];

void solve(string x, string y)
{
	for (int i = 0; i != x.size(); i++)
	{
		for (int j = 0; j != y.size(); j++)
		{
			if (x[i] == y[j])
			{
				LCS[i + 1][j + 1] = LCS[i][j] + 1;
			}
			else
			{
				LCS[i + 1][j + 1] = max(LCS[i][j + 1], LCS[i + 1][j]);
			}
		}
	}

	cout << LCS[x.size()][y.size()] << endl;
}

int main()
{
	int q;
	cin >> q;

	for (int i = 0; i < 1000; i++)
	{
		LCS[0][i] = 0;
		LCS[i][0] = 0;
	}

	for (int i = 0; i < q; i++)
	{
		string x, y;
		cin >> x >> y;
		solve(x, y);
	}
	return 0;
}

C++: #include <iostream>
#include <string>
#include <utility>
#include <algorithm>
#include <vector>
#include <cstdio>
#include <cstring>

using namespace std;

string s1,s2;

int L(int i,int j){
	if(i<=0||j<=0)return 0;
	else if(s1.at(i)==s2.at(j))return 1+L(i-1,j-1);
	else{
		return L(i,j-1)>L(i-1,j)?L(i,j-1):L(i-1,j);
	}
}

int main(){
	int q;
	cin>>q;
	for(int i=0; i<q; i++){
		cin>>s1>>s2;
		cout<<L(s1.size()-1,s2.size()-1)+1<<endl;
	}
}

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

static const int 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;
}

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

using namespace std;

int main() {
	int q;
	string strX, strY;

	cin >> q;
	for (int n = 0; n < q; n++) {
		cin >> strX;
        cin >> strY;
		char X[strX.length() + 1];
		for (int x = 0; x < strX.length(); x++) {//文字列を配列に入れる
			X[x + 1] = strX[x];
		}

        char Y[strY.length() + 1];
		for (int y = 0; y < strY.length(); y++) {//文字列を配列に入れる
			Y[y + 1] = strY[y];
		}

        int c[strX.length()+1][strY.length()];
        int maxLen = 0;

		for (int i = 0; i<=strX.length(); i++){
            for(int j = 0; j<=strY.length(); j++){
                if(i == 0 || j == 0){
                    c[i][j] = 0;
                }
                else 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]);
                }

                if(c[i][j] > maxLen){
                    maxLen = c[i][j];
                }
            }
        }
        cout << maxLen << endl;
	}

    return 0;
}

C++: #include <bits/stdc++.h>
#define debug(x) cerr << #x << ": " << x << '\n';
using namespace std;
using ll = long long;
using P = pair<int, int>;
const int INF = (int)1e9;
const int MOD = (int)1e9 + 7;

int dp[1001][1001];

int main(void){
	int q;
	cin >> q;

	vector<int> res;
	for(int i = 0; i < q; i++){
		string s, t;
		cin >> s >> t;

		fill(dp[0], dp[1000] + 1000, 0);
		for(int j = 0; j < s.size(); j++){
			for(int k = 0; k < t.size(); k++){
				if(s[j] == t[k]) dp[j+1][k+1] = dp[j][k] + 1;
				else dp[j+1][k+1] = max(dp[j+1][k], dp[j][k+1]);
			}
		}

		res.push_back(dp[s.size()][t.size()]);
	}

	for(int i = 0; i < q; i++) cout << res[i] << '\n';

	return 0;
}

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

int dp[1001][1001];
string str1, str2;
int n;

int solve(string str1, string str2) {
  memset(dp, 0, sizeof(dp));
  for(int r = 0; r < str2.size(); r++) {
    for(int c = 0; c < str1.size(); c++) {
      if(str2[r] == str1[c]) {
        dp[r + 1][c + 1] = dp[r][c] + 1;
      }
      else {
        dp[r + 1][c + 1] = max(dp[r + 1][c], dp[r][c + 1]);
      }
    }
  }
  return dp[str2.size()][str1.size()];
}

int main() {
  cin >> n;
  for(int i = 0; i < n; i++) {
    cin >> str1 >> str2;
    cout << solve(str1, str2) << endl;
  }
}

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

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    int n;
    std::cin >> n;
    std::string s1, s2;
    for (int q=0; q<n; q++) {
        std::cin >> s1 >> s2;
        int m1 = s1.size()+1;
        int m2 = s2.size()+1;
        int* dp = (int*)malloc(m1*m2*sizeof(int));
        for (int i=0; i<m1; i++) {
            dp[i*m2]=0;
        }
        for (int i=0; i<m2; i++) {
            dp[i]=0;
        }
        for (int i=1; i<m1; i++) {
            int leftmax=0;
            for (int j=1; j<m2; j++) {
                dp[i*m2+j] = leftmax;
                if (s1[i-1] == s2[j-1]) {
                    dp[i*m2+j]+=1;
                }
                if (dp[(i-1)*m2+j] > leftmax) {
                    leftmax = dp[(i-1)*m2+j];
                }
                if (dp[i*m2+j] < dp[(i-1)*m2+j]) {
                    dp[i*m2+j] = dp[(i-1)*m2+j];
                }
            }
        }
        int max=0;
        for (int i=0; i<m2; i++) {
            if (dp[(m1-1)*m2+i] > max) {
                max = dp[(m1-1)*m2+i];
            }
        }
        std::cout << max << "\n";
        free(dp);
    }

    return 0;
}

C++: #include<iostream>
#include<cstring>
#include<string>
#include<algorithm>
using namespace std;
const int maxn = 1005;

int dp[maxn][maxn];
int len1, len2;
string s1, s2;

int lcs()
{
	memset(dp, 0, sizeof(dp));
	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]);
			}
		}
	return dp[len1][len2];
}

int main()
{
	int n;
	cin >> n;
	while (n--)
	{
		cin >> s1 >> s2;
		len1 = s1.size(), len2 = s2.size();
		cout << lcs() << endl;
	}
	return 0;
}