Go: package main

import "fmt"

func main() {
	var nPairs int
	fmt.Scanln(&nPairs)

	var a, b string
	for i := 0; i < nPairs; i++ {
		fmt.Scanln(&a)
		fmt.Scanln(&b)
		fmt.Println(lcsSize(a, b))
	}
}

func lcsSize(sa, sb string) int {
	dp := make([][]int, len(sa)+1)
	for i := 0; i <= len(sa); i++ {
		dp[i] = make([]int, len(sb)+1)
	}

	for a := 1; a <= len(sa); a++ {
		for b := 1; b <= len(sb); b++ {
			if sa[a-1] == sb[b-1] {
				dp[a][b] = dp[a-1][b-1] + 1
			} else {
				dp[a][b] = max(dp[a][b-1], dp[a-1][b])
			}
		}
	}

	return dp[len(sa)][len(sb)]
}

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

C++: #include <iostream>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <functional>
#include <vector>
#include <list>
#include <queue>
#include <deque>
#include <stack>
#include <map>
#include <set>
#include <bitset>
#include <tuple>
#include <cassert>
#include <exception>
#include <iomanip>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> P;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<string> vs;
typedef vector<P> vp;
#define rep(i,a,n) for(ll i = (a);i < (n);i++)
#define per(i,a,n) for(ll i = (a);i > (n);i--)
#define lep(i,a,n) for(ll i = (a);i <= (n);i++)
#define pel(i,a,n) for(ll i = (a);i >= (n);i--)
#define clr(a,b) memset((a),(b),sizeof(a))
#define pb push_back
#define mp make_pair
#define all(c) (c).begin(),(c).end()
#define sz size()
#define print(X) cout << (X) << endl
#define fprint(NUM,X) cout << fixed << setprecision(NUM) << (X) << endl
#define fprints(NUM,X,Y) cout << fixed << setprecision(NUM) << (X) << " " << (Y) << endl
const ll INF = 1e+9+7;
ll n,m,l;
string s,t;
ll d[200010],dp[1000][1000];
double w[1000],v[1000];
double box[200010];

ll fib(int i){
  if(i == 1 || i == 0)return 1;
  if(d[i] != 0)return d[i];
  return d[i] = fib(i-1) + fib(i-2);
}

int main(){
  cin >> n;
  rep(i,0,n){
    cin >> s >> t;
    clr(dp,0);
    rep(k,0,s.sz){
      rep(j,0,t.sz){
        if(s[k] == t[j]){
          dp[k+1][j+1] = dp[k][j] + 1;
        }else{
          dp[k+1][j+1] = max(dp[k+1][j] , dp[k][j+1]);
        }
      }
    }
    print(dp[s.sz][t.sz]);
  }
  return 0;
}

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


int main(int argc, char *argv[]){
  int n;
  cin >> n;
  for (int r = 0; r < n; r++) {

    string x, y;
    cin >> x >> y;
    int dp[y.length() + 1][x.length() + 1];
    memset(dp, 0, sizeof(dp));
    for (int i = 0; i < y.length(); i++) {
      for (int j = 0; j < x.length(); j++) {
        if(y[i] == x[j]){
          dp[i + 1][j + 1] = dp[i][j] + 1;
        }else{
          dp[i + 1][j + 1] = max(dp[i + 1][j], dp[i][j + 1]);
        }
      }
    }
    std::cout << dp[y.length()][x.length()] << std::endl;
  }
  return 0;
}

C++: #include "bits/stdc++.h"
#define REP(i, n) for(int i = 0; i < n; i++)
#define REPR(i, n) for(int i = n; i >= 0; i--)
#define FOR(i, m, n) for(int i = m; i < n; i++)
#define FORR(i, a, b) for(int i=(b)-1; i>=(a); --i)
#define ALL(v) v.begin(), v.end()
#define FS first
#define SC second
#define SZ(a) int((a).size())
#define SORT(c) sort((c).begin(),(c).end())
#define MEMSET(v, h) memset((v), h, sizeof(v))
#define SQR(x) ((x) * (x))
#define BIT(n) (1LL<<(n))
#define PCNT(x) __builtin_popcountll(x)
#define PB push_back
#define MP make_pair
#define endl "\n"
using namespace std;
typedef long long LL;
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<bool> VB;
typedef vector<vector<int> > VVI;
typedef vector<vector<bool> > VVB;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;
const LL MOD=1000000007ll;
const LL INF=2000000000ll;
template <class T> bool chmax( T& a, T b );
template <class T> bool chmin( T& a, T b );
int dx[4] = {1,0,-1,0};
int dy[4] = {0,1,0,-1};

long power(long a,long b){return b?power(a*a%MOD,b/2)*(b%2?a:1)%MOD:1;}

long perm(int N, int K){
	long x=1;
	for(int i=1;i<=K;i++)
	{
		x=x*(N-i+1)%MOD;
	}
	return x%MOD;
}

long factorial(int N){
	return perm(N,N);
}

long comb(int N,int K){
	long x=1,y=1;
	for(int i=1;i<=K;i++)
	{
		x=x*(N-i+1)%MOD;
		y=y*i%MOD;
	}
	return x*power(y,MOD-2)%MOD;
}

long hcomb(int N, int K){
    return comb(N+K-1, N-1);
}

bool isprime(int n) {
    if (n < 2) return false;
    for (int i = 2; i*i <= n; ++i) {
        if (n % i ==  0) return false;
    }
    return true;
}

void eratosthenes(int n){
	// エラトステネスのふるい
    bitset<1000000> is_prime(0); // 十分大きなサイズを確保します
    for (int i = 2; i <= n; ++i) is_prime.set(i); // とりあえず全部ふるいに入れます
    for (int i = 2; i <= n; ++i) {
        if (is_prime[i]) { // 素数 i を発見したら
            for (int j = i * 2; j <= n; j += i) {
                is_prime.reset(j); // i の倍数をふるい落とす
            }
        }
    }
	for (int i = 2; i <= n; ++i) {
        if (is_prime[i]) cout << i << endl;
    }
}

void dfs(const vector<vector<int> > &G, int v, vector<int> &seen) {
    seen[v] = true; // v を訪問済にする

    // v から行ける各頂点 next_v について
    for (int next_v : G[v]) { 
        if (seen[next_v]) continue; // next_v が探索済だったらスルー
        dfs(G, next_v, seen); // 再帰的に探索
    }
}

void bfs(const vector<vector<int> > &G, int v, vector<int> &dist){
    REP(i,SZ(dist)) dist[i] = -1; // 全頂点を「未訪問」に初期化
    queue<int> que;

    // 初期条件 (頂点 0 を初期ノードとする)
    dist[v] = 0;
    que.push(v); // 0 を橙色頂点にする

    // BFS 開始 (キューが空になるまで探索を行う)
    while (!que.empty()) {
        v = que.front(); // キューから先頭頂点を取り出す
        que.pop();

        // v から辿れる頂点をすべて調べる
        for (int next_v : G[v]) {
            if (dist[next_v] != -1) continue; // すでに発見済みの頂点は探索しない

            // 新たな白色頂点 nv について距離情報を更新してキューに追加する
            dist[next_v] = dist[v] + 1;
            que.push(next_v);
        }
    }
}

int knapsack01(int N, int W, vector<int> &value, vector<int> &weight){
    VVI dp(N+1,VI(W+1,0));
    REP(i,N) REP(j,W+1){
        if (j-weight[i] >= 0) dp[i+1][j] = max(dp[i][j-weight[i]] + value[i], dp[i][j]);
        else dp[i+1][j] = dp[i][j];
    }
    return dp[N][W];
}

int knapsack01_reuse(int N, int W, vector<int> &value, vector<int> &weight){
    VI dp(W+1,0);
    dp[0] = 0;
    for (int i = 0; i < N; i++){
        for (int j = W ;j > 0; j--){
            if (j-weight[i] >= 0) dp[j] = max(dp[j],dp[j-weight[i]]+value[i]);
        }
    }
    return dp[W];
}

int knapsack(int N, int W, vector<int> &value, vector<int> &weight){
    VVI dp(N+1,VI(W+1,0));
    REP(i,N) REP(j,W+1){
        dp[i+1][j] = max(dp[i][j],dp[i+1][j]);
        if (j-weight[i] >= 0) dp[i+1][j] = max(dp[i+1][j-weight[i]]+value[i], dp[i+1][j]); 
    }
    return dp[N][W];
}

int knapsack_reuse(int N, int W, vector<int> &value, vector<int> &weight){
    VI dp(W+1,0);
    dp[0] = 0;
    for (int i = 0; i < N; ++i) {
        for (int w = weight[i]; w <= W; ++w) {
            dp[w] = max(dp[w], dp[w - weight[i]] + value[i]);
        }
    }
    return dp[W];
}

int lis(int n, vector<int> &A){
    vector<int> L(n+1,0);
    L[0] = A[0];
    int length = 1;

    FOR(i,1,n){
        if (L[length-1] < A[i]) L[length++] = A[i];
        else *lower_bound(L.begin(),next(L.begin(),length),A[i]) = A[i];
    }

    return length;
}

int lcs(string X, string Y){
    int m = X.length();
    int n = Y.length();
    int res = 0;
    X = ' ' + X;
    Y = ' ' + Y;
    VVI c(m+1, VI(n+1,0));
    FOR(i,1,m+1) FOR(j,1,n+1){
        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]);
        res = max(res,c[i][j]);
    }
    return res;
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout << fixed << setprecision(10);

    int q;
  	cin >> q;
    string X,Y;
    REP(i,q){
        cin >> X >> Y;
        cout << lcs(X,Y) << endl;
    }                                                                                       
}