#include<bits/stdc++.h>
#define arrout(a, n) rep(i, 1, n) printk(a[i])
#define arrin(a, n) rep(i, 1, n) a[i] = read()
#define rep(i, x, n) for(int i = x; i <= n; i ++)
#define dep(i, x, n) for(int i = x; i >= n; i --)
#define erg(i, x) for(int i = head[x]; i; i = e[i].nex)
#define dbg(x) std::cout << #x << ":" << x << " "
#define mem(a, x) memset(a, x, sizeof a)
#define arrall(a, n) a + 1, a + 1 + n
#define all(x) x.begin(), x.end()
#define PII std::pair<int, int>
#define m_p std::make_pair
#define l_b lower_bound
#define u_b upper_bound
#define p_b push_back
#define CD const double
#define CI const int
#define ll long long
#define il inline
#define ss second
#define ff first
#define itn int
#define v void
using namespace std;
il v read(int &a){
	int f=0;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-'){
			f=1;
		}
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		a=((a<<1)+(a<<3))+(c^48);
		c=getchar();
		if(c==-1 or c=='\n'){
			break;
		}
		if(f==1){
			a=-a;
		}
	}
}
il v write(int a){
	int f=0;
	if(a<0){
		a=-a;
		f=1;
	}
	if(a==0){
		if(f==1)
			cout<<"-";
		return;
	}
	write(a/10);
	putchar(char(a%10+'0'));
}
itn main(){
	ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
	return 0;
}