my 洛谷

#include <bits/stdc++.h>
#define ll long long
#define endl '\n'
#define itn int
#define vi void
#define il inline
#define I using
#define will namespace
#define ak std
#define IOI ;

I will ak IOI

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	
	return 0;
}

-std=c++14 -O2 -Wall -Wextra -fno-ms-extensions