Go: package main

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

var (
	nstr   func() string
	stdout *bufio.Writer
)

func init() {
	nstr = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func main() {
	defer stdout.Flush()

	n := nint()
	xList := make([]string, n)
	yList := make([]string, n)

	for i:=0;i<n ;i++  {
		xList[i] = nstr()
		yList[i] = nstr()
	}

	for i := 0; i<n	; i++  {
		fmt.Println(lcs(xList[i], yList[i]))
	}

}

func lcs(x string, y string) int{
	var m = len(x)
	var n = len(y)

	c := make([][]int, m+1)
	for i:= range c{
		c[i] = make([]int, n+1)
	}
	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] = int(math.Max(float64(c[i-1][j]), float64(c[i][j-1])))
			}


		}
	}
	return c[m][n]

}


func newReadString(ior io.Reader) func() string {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), int(1e+11))
	r.Split(bufio.ScanWords)

	return func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
}

func nint64() int64 {
	i, err := strconv.ParseInt(nstr(), 0, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func nint() int {
	return int(nint64())
}

func getIntSlice(n int) []int {
	b := make([]int, n)
	for i := 0; i < n; i++ {
		b[i] = nint()
	}
	return b
}

func getStringSlice(n int) []string {
	b := make([]string, n)
	for i := 0; i < n; i++ {
		b[i] = nstr()
	}
	return b
}

func gcd(x, y int) int {
	if y == 0 {
		return x
	}
	return gcd(y, x%y)
}

func lcm(x, y int) int {
	return x * y / gcd(x, y)
}

func contains(s []int, e int) bool {
	for _, a := range s {
		if a == e {
			return true
		}
	}
	return false
}

func bin(i int, prefix bool) string {
	i64 := int64(i)

	if prefix {
		return "0b" + strconv.FormatInt(i64, 2)
	} else {
		return strconv.FormatInt(i64, 2)
	}
}

func strReverse(s string) string {
	runes := []rune(s)
	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
		runes[i], runes[j] = runes[j], runes[i]
	}

	return string(runes)
}

C++: #include <stdio.h>
#include <iostream>
#include <algorithm>

using namespace std;

short checkTable[1001][1001];

int tmp_max=0;


void calc(int index,char pattern[],char to_search[],int to_search_length){

	for(int i=to_search_length-1;i>=0;i--){
		if(to_search[i]==pattern[index]){
			checkTable[index][i]=1;
			if(pattern[index+1]!='\0' && i < to_search_length-1){
				checkTable[index][i] = checkTable[index+1][i+1] + checkTable[index][i];
			}
		}else{
			if(i != to_search_length-1){
				if(pattern[index+1] != '\0'){
					checkTable[index][i]=(checkTable[index+1][i]>checkTable[index][i+1])
							?checkTable[index+1][i]:checkTable[index][i+1];

				}else{
					checkTable[index][i]=(checkTable[index][i+1]>0)?checkTable[index][i+1]:0;
				}
			}else{
				if(pattern[index+1] != '\0'){
					checkTable[index][i]=(checkTable[index+1][i]>0)?checkTable[index+1][i]:0;
				}else{
					checkTable[index][i] = 0;
				}
			}
		}
		tmp_max = (tmp_max >= checkTable[index][i])?tmp_max:checkTable[index][i];
	}
}

int main(){

	int q,left_length,right_length;
	char left[1001],right[1001];

	scanf("%d",&q);

	for(int i=0;i<q;i++){
		left_length=0;
		right_length=0;
		scanf("%s %s",left,right);
		for(int k=0;left[k]!='\0';k++)left_length++;
		for(int k=0;right[k]!='\0';k++)right_length++;

		if(right_length>=left_length){

			for(int k=left_length-1;k>=0;k--)calc(k,left,right,right_length);
		}else{

			for(int k=right_length-1;k>=0;k--)calc(k,right,left,left_length);
		}
		printf("%d\n",tmp_max);
		tmp_max=0;
	}

    return 0;
}

C++: #include <iostream>
#define MAX 1010

int C[MAX][MAX];

int main() {
  int n;
  std::cin >> n;
  int answers[160];

  for(int m=0; m<n; ++m) {
    std::string X;
    std::string Y;
    std::cin >> X;
    std::cin >> Y;

    // initialize
    for(int k=0; k<MAX; ++k) {
      for(int j=0; j<MAX; ++j) C[k][j] = 0;
    }

    // lcs
    int xlen = X.size();
    int ylen = Y.size();

    for(int i=1; i<=xlen; ++i) {
      for(int j=1; j<=ylen; ++j) {
        if(X[i] == Y[j]) {
          C[i][j] = C[i-1][j-1] + 1;
        } else {
          C[i][j] = std::max(C[i-1][j], C[i][j-1]);
        }
      }
    }

    answers[m] = C[xlen][ylen];
  }

  for(int h=0; h<n; ++h) {
    std::cout << answers[h] << std::endl;
  }
}

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

		return 0;
	}

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

int lcs(string X, string Y) {
  int dp[1000 + 1][1000 + 1];
  int max = 0;
  int m = X.size();
  int n = Y.size();
  X = ' ' + X;
  Y = ' ' + Y;

  for (int i = 1; i <= m; i++)
    dp[i][0] = 0;

  for (int i = 1; i <= n; i++)
    dp[0][i] = 0;

  for (int i = 1; i <= m; i++) {
    for (int j = 1; j <= n; j++) {
      if (X[i] == Y[j])
	dp[i][j] = dp[i-1][j - 1] + 1;
      else if (dp[i - 1][j] >= dp[i][j - 1])
	dp[i][j] = dp[i - 1][j];
      else
	dp[i][j] = dp[i][j - 1];

      max = (max < dp[i][j]) ? dp[i][j] : max;
    }
  }

  return max;
}

int main(int argc, char const *argv[]) {
  int N;
  cin >> N;

  for (int i = 0; i < N; i++) {
    string X, Y;
    cin >> X >> Y;

    cout << lcs(X, Y) << endl;
  }

  return 0;
}

C++: #include <iostream>
#define MAX 1010

int C[MAX][MAX];

int main() {
  int n;
  std::cin >> n;
  int answers[160];

  for(int m=0; m<n; ++m) {
    std::string X;
    std::string Y;
    std::cin >> X;
    std::cin >> Y;

    // initialize
    for(int k=0; k<MAX; ++k) {
      for(int p=0; p<MAX; ++p) C[k][p] = 0;
    }

    // lcs
    int xlen = X.size();
    int ylen = Y.size();

    X = ' ' + X;
    Y = ' ' + Y;

    for(int i=1; i<=xlen; ++i) {
      for(int j=1; j<=ylen; ++j) {
        if(X[i] == Y[j]) {
          C[i][j] = C[i-1][j-1] + 1;
        } else {
          C[i][j] = std::max(C[i-1][j], C[i][j-1]);
          
        }
      }
    }

    answers[m] = C[xlen][ylen];
  }

  for(int h=0; h<n; ++h) {
    std::cout << answers[h] << std::endl;
  }
}

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

constexpr 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;

   //c[i][j]のためにX[0],Y[0]に空白を挿入
   X=' '+X;
   Y=' '+Y;
   for(int i=1; i<m+1; i++) c[i][0]=0;
   for(int j=1; j<n+1; j++) c[0][j]=0;

   for(int i=1; i<m+1; i++){
      for(int j=1; j<n+1; 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(){
   string x, y;
   int n; cin >> n;
   for(int i=0; i<n; i++){
      cin >> x;
      cin >> y;
      cout << lcs(x, y) << endl;
   }

   return 0;
}