常用头文件

#include<bits/stdc++.h>
#define INF 0x3f3f3f3f
#define DOF 0x7f7f7f7f
#define endl ‘\n‘
#define mem(a,b) memset(a,b,sizeof(a))
#define debug(x) cout<<"This is "<<x<<‘\n‘
#define IO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
typedef long long ll;
using namespace std;

int main()
{
    return 0;
}

#include <iostream>
#include<algorithm>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#include<map>
#include<set>
#include<stack>
#include<sstream>
#define endl ‘\n‘
#define debug(x) cout<<"This is "<<x<<‘\n‘
#define INF 0x3f3f3f3f
#define DOF 0x7f7f7f7f
#define mem(a,b) memset(a,b,sizeof(a))
#define IO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
typedef long long ll;
using namespace std;

int main()
{
    return 0;
}