void read(int &ans)
{
	char c;
	ans = 0;
	while ((c = getchar()) < '0' || c > '9');
	while (c >= '0'&&c <= '9')
	{
		ans = ans * 10 + (c - '0');
		c = getchar();
	}
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    std::ios::sync_with_stdio(false);
    return 0;
}