Go: package main

import (
	. "fmt"
    "math"
)

// func init() { Println("----------------------------------------") }

func main() {
    const L_MAX = 1003

	var q int
	Scanf("%d", &q)
	X := make([]string, 0, 150)
	Y := make([]string, 0, 150)
	for i := 0; i < 2 * q; i++ {
	    var tmp string
	    Scanf("%s", &tmp)

	    if i % 2 == 0 {
	        X = append(X, tmp)
	    } else {
	        Y = append(Y, tmp)
	    }
	}

    for i := 0; i < q; i++ {
        dp := make([][]int, L_MAX)
        for k, _ := range dp {
            dp[k] = make([]int, L_MAX)
        }

        x, y := X[i], Y[i]

        // init
        isXFound := false
        for c := 0; c < len(x); c++ {
            if isXFound || y[0] == x[c] {
                dp[0][c] = 1
                isXFound = true
            }
        }
        isYFound := false
        for r := 0; r < len(y); r++ {
            if isYFound || x[0] == y[r] {
                dp[r][0] = 1
                isYFound = true
            }
        }

        for r := 1; r < len(y); r++ {
            for c := 1; c < len(x); c++ {
                // dp[r][c]
                if x[c] == y[r] {
                    dp[r][c] = int(math.Max(float64(dp[r - 1][c - 1] + 1), float64(dp[r][c])))
                }

                dp[r][c] = int(math.Max(float64(dp[r][c]), math.Max(float64(dp[r - 1][c]), float64(dp[r][c - 1]))))
            }
        }
        Println(dp[len(y) - 1][len(x) - 1])

        // LCSも求めておく
        // ans := ""
        // r, c := len(y) - 1, len(x) - 1
        // for r >= 0 && c >= 0 {
        //     if y[r] == x[c] {
        //         ans = string(x[c]) + ans
        //         r--
        //         c--
        //     } else {
        //         if dp[r - 1][c] > dp[r][c - 1] {
        //             r--
        //         } else {
        //             c--
        //         }
        //     }
        // }
        // Println(ans)
    }
}

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 = 0; 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 <algorithm>
#include <cstdio>
#include <cmath>
#include <string>
#include <cctype>
#include <stack>
#include <queue>
#include <vector>
#include <cstdlib>

using namespace std;


int main(void) {

	char X[100], Y[100];
	char *S;
	int q;

	cin >> q;

	for (int i = 0;i < q;i++) {
		cin >> X;
		cin >> Y;
		S = strstr(X, Y);
		cout << strlen(S) << endl;
	}
		return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

#define Vi vector<int>
#define FOR(i,s,e) for (int i=s; i<e; i++)
#define ITER(v) v.begin(), v.end()

constexpr int MAX_LEN = 1'000;
int dp[MAX_LEN][MAX_LEN];

void set_val(int i, int j, int inc) {
    int val = inc;
    if (i > 0 && j > 0) {
        int tmp = dp[i-1][j-1] + inc;
        val = max(val, tmp);
    }
    if (i > 0) {
        int tmp = dp[i-1][j];
        val = max(val, tmp);
    }
    if (j > 0) {
        int tmp = dp[i][j-1];
        val = max(val, tmp);
    }
    dp[i][j] = val;
    //cout << i << " " << j << " " << val << endl;
}

int lcs(const string& x, const string& y) {
    int lx = x.length();
    int ly = y.length();
    for (int i=0; i<lx; ++i) {
        for (int j=0; j<ly; ++j) {
            if (x[i] == y[j]) {
                set_val(i, j, 1);
            } else {
                set_val(i, j, 0);
            }
        }
    }
    return dp[lx-1][ly-1];
}

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

    int n;
    cin >> n;

    string x, y;
    FOR(i,0,n) {
        cin >> x;
        cin >> y;
        cout << lcs(x, y) << endl;
    }

    return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<cstdlib>
#include <cmath>
#include<stdio.h>
#include<queue>
#define MAX 1000000000000000000LL
long long inf=1000000007;
using namespace std;

int lcs(string X,string Y){
    int  c[1001][1001];
    long long m=X.size();
    long long 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 <cstdio>
#include <iostream>
#include <string>
#include <vector>

using namespace std;

#define pb push_back

typedef vector<int> vi;
typedef vector<vector<int> > vvi;

int lcs(string a, string b) {
  vvi len(a.length()+1, vi(b.length()+1, 0));
  for (int ia = 1 ; ia <= a.length() ; ia++) {
    for (int ib = 1 ; ib <= b.length() ; ib++) {
      if (a[ia-1] == b[ib-1]) {
        len[ia][ib] = len[ia-1][ib-1]+1;
      } else {
        len[ia][ib] = max(len[ia][ib-1], len[ia-1][ib]);
      }
    }
  }
  return len[a.length()][b.length()];
}

int main() {
  int t;
  cin >> t;
  vi results;
  for (int dataset = 0 ; dataset < t ; dataset++) {
    string a, b;
    cin >> a;
    cin >> b;
    results.pb(lcs(a, b));
  }

  for (int it = 0 ; it < t ; it++) {
    printf("%d\n", results[it]);
  }

  return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

#define FOR(i,s,e) for((i)=(s);(i)<(int)(e);(i)++)
#define REP(i,e) FOR(i,0,e)

#define all(o) (o).begin(), (o).end()
#define psb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))

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

const double EPS = 1e-10;

const int N = 1000;
char s[N+1], t[N+1];
int ls, lt;
int q;
int dp[N+1][N+1];
//dp[i][j] = s[0]...s[i-1]??¨t[0]...t[j-1]???LCS
//(1<=i<=ls, 1<=j<=lt)

int main() {
  int i, j, k;
  scanf("%d ", &q);
  for (k=0; k<q; k++) {
    ls = lt = 0;
    memset(s, 0, sizeof(s)), scanf("%s ", s);
    memset(t, 0, sizeof(t)), scanf("%s ", t);
    while (s[ls]) ls++;
    while (t[lt]) lt++;

    memset(dp, 0, sizeof(dp));
    for (i=1; i<=ls; i++)
      for (j=1; j<=lt; j++) {
        if (s[i-1]==t[j-1])
          dp[i][j] = dp[i-1][j-1] + 1;
        else
          dp[i][j] = max(dp[i-1][j], dp[i][j-1]);
      }

    printf("%d\n", dp[ls][lt]);
  }

  return 0;
}