常用宏定义头文件，节省时间

#include <algorithm>
#include <cstdio>
#include <iostream>
#include <string>
#include <cmath>
#include <cstring>
#include <deque>
#include <queue>
#include <vector>
#include <stack>
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define REP(i,n) for(int i=0;i<(n);i++)
#define siz(x) ((int)x.size())
#define fi first
#define se second
#define pb push_back
#define mp make_pair
using namespace std;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef long long ll;

template<class T> inline void read(T &x){
	int f=0;x=0;char ch=getchar();
	for(;!isdigit(ch);ch=getchar())f|=(ch=='-');
	for(;isdigit(ch);ch=getchar())x=x*10+ch-'0';
	if(f)x=-x;
}

int main(){
	
	return 0;
}