C++ Template

#include <iostream>
#include <string>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <regex>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <unordered_map>
#include <numeric>
#include <iomanip>
using namespace std;
#define pii pair<int, int>
#define ll long long
#define FAST ios_base::sync_with_stdio(false); cin.tie(NULL)
#define mp(x1, x2) ( make_pair(x1, x2) )
const int dx[4] = {1, 0, 0, -1}, dy[4] = {0, 1, -1, 0};
const int dl[2] = {1, -1};
const int MOD = 100000007;
const int MAXN = 202020;

int main(){
    FAST;
    freopen("combo.in", "r", stdin);
    freopen("combo.out", "w", stdout);
}