Go: package main

/*
最長共通部分列
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"
)

func larger(l, r int) int {
	if l > r {
		return l
	}
	return r
}

var memo [1001][1001]int

func countLCS(x, y string) int {
	x = " " + x
	y = " " + y
	max := 0
	for xi := 1; xi < len(x); xi++ {
		for yi := 1; yi < len(y); yi++ {
			if x[xi] == y[yi] {
				memo[xi][yi] = memo[xi-1][yi-1] + 1
			} else {
				memo[xi][yi] = larger(memo[xi-1][yi], memo[xi][yi-1])
			}
			max = larger(max, memo[xi][yi])
		}
	}
	return max
}

func main() {
	scanner := makeScanner(1024)
	q := eGetInt(scanner)
	for i := 0; i < q; i++ {
		x := eGetLine(scanner)
		y := eGetLine(scanner)
		fmt.Println(countLCS(x, y))
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}
func min(a []int) int {
	m := a[0]
	for _, v := range a {
		if v < m {
			m = v
		}
	}
	return m
}

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

C++: #include <string>
#include <iostream>
#include <algorithm>
using namespace std;
int q, n, m, dp[1007][1007]; string s, t;
int main() {
	cin >> q;
	while(q--) {
		cin >> s >> t;
		n = s.size(), m = t.size();
		for(int i = 1; i <= n; i++) {
			for(int j = 1; j <= m; j++) {
				dp[i][j] = (s[i - 1] == t[j - 1] ? dp[i - 1][j - 1] + 1 : max(dp[i - 1][j], dp[i][j - 1]));
			}
		}
		cout << dp[n][m] << endl;
	}
}

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

#define rep(i,n) for(int i=0;i<(n);i++)

template<class T>
bool chmax(T &a, const T &b) {
    if(a<b) {
        a=b;
        return false;
    }
    return true;
}

using namespace std;

int dp[1003][1003];
int main() {
    int q; cin>>q;
    rep(_,q) {
        memset(dp,0,sizeof(dp));
        string s,t;
        cin>>s>>t;
        s=" "+s;
        t=" "+t;
        rep(i,s.size()){
            rep(j,t.size()) {
                if(i&&j) {
                    if(s[i]==t[j]) dp[i][j]=dp[i-1][j-1]+1;
                    else {
                        chmax(dp[i][j],dp[i-1][j]);
                        chmax(dp[i][j],dp[i][j-1]);
                    }
                }
            }
            //rep(j,t.size()) cout<<dp[i][j]<<" ";
            //cout<<endl;
        }
        int ans=0;

        rep(i,s.size()) chmax(ans,*max_element(dp[i],dp[i]+t.size()));
        cout<<ans<<endl;
    }

    return 0;
}

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

using namespace std;



int n;
string a, b;
string x[1000], y[1000];




int main(){
  cin >> n;
  while(n != 0){
    n = n -1;
    int longest[1000][1000];
    cin >> a;
    cin >> b;
    a = ' ' + a;
    b = ' ' + b;
    int mm = 0;
    
   for(int i = 1; i <= a.size(); ++i){
     longest[i][0] = 0;
    }
   for(int j = 1; j <= b.size(); ++j){
     longest[0][j] = 0;
   }
    for(int i = 1; i <= a.size(); ++i){
      for(int j = 1; j <= b.size(); ++j){
        
        
        if(a[i] == b[j]){
          longest[i][j] = 1 + longest[i-1][j - 1];
        }
        else{
          longest[i][j] = max(longest[i][j-1], longest[i-1][j]);
        }
        mm = max(mm, longest[i-1][j-1]);
      }
    }
    //cout << a[1] << endl;
    cout << mm << endl;
  }
}

C++: #include <cstdio>
#include <algorithm>
#include <vector>
#include <string>

class TLcsSolver
{
    typedef std::vector<std::vector<int> > TTable;
    TTable FTable;
    std::string FArray1;
    std::string FArray2;

    int Count(int i, int j)
    {
        if(i == 0 || j == 0) return 0;
        if(FArray1[i-1] == FArray2[j-1]){
            return FTable[i-1][j-1] + 1;
        }
        return std::max(FTable[i-1][j], FTable[i][j-1]);
    }
    void Solve()
    {
        for(std::size_t i = 1; i < FTable.size(); ++i){
            for(std::size_t j = 1; j < FTable[i].size(); ++j){
                FTable[i][j] = Count(i, j);
            }
        }
    }
public:
    TLcsSolver(const std::string& a, const std::string& b)
     : FArray1(a), FArray2(b)
     , FTable(a.size()+1, std::vector<int>(b.size()+1, 0))
    {
        Solve();
    }
    int Answer()const
    {
        return FTable[FArray1.size()][FArray2.size()];
    }
};

int main()
{
    int n;
    std::scanf("%d", &n);
    char a[1000];
    char b[1000];
    for(int i = 0; i < n; ++i){
        std::gets(a);
        std::gets(b);
        std::printf("%d", TLcsSolver(a, b).Answer());
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
int n,m,p;
string s,t;

int main(){
    cin >> p;
    for(int i=0;i<p;i++){
        cin >> s >> t;
        n=s.size();
        m=t.size();
        vector<int> memo(m+1,0);
        for(int j=0;j<n;j++){
            vector<int> memo2(m+1,0);
            for(int k=0;k<m;k++){
                memo2[k]=max(memo2[k],memo[k]);
                memo[k+1]=max(memo[k+1],memo[k]);
                memo2[k+1]=memo[k]+(s[j]==t[k]);
            }
            memo2[m]=max(memo2[m],memo[m]);
            for(int k=0;k<m+1;k++){
                memo[k]=memo2[k];
            }
        }
        int c=0;
        for(int j=0;j<m+1;j++){
            c=max(memo[j],c);
        }
        cout << c << endl;
    }
}

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

int main(void){
  string st1, st2;
  int q, val[1001][1001];

  cin >> q;

  for(int i=0; i<q; i++){
    cin>>st1;
    cin>>st2;

    for(int j=0; j<=st1.length(); j++){
      for(int k=0; k<=st2.length(); k++){

	if(j==0 || k==0) val[j][k] = 0;
	else{
	  if(val[j-1][k] == min(st1.length(), st2.length())){
	    val[j][k] = st1.length();
	  }else{

	    if(st1[j-1] == st2[k-1]){
	      val[j][k] = val[j-1][k-1]+1;
	    }else{
	      val[j][k] = max(val[j-1][k], val[j][k-1]);
	    }
	  }
	}
      }
    }

    /*
      for(int j=0; j<=st1.length(); j++){
      for(int k=0; k<=st2.length(); k++){
      cout << val[j][k] << " ";
      }
      cout << "\n";
      }
    */

    cout << val[st1.length()][st2.length()] << "\n";
  }

  return 0;
}