Submission

Score: 0

User: qweqwe

Problemset: ขนมของเซ้น143 (v.ยาก)

Language: cpp

Time: 0.002 second

Submitted On: 2025-10-16 20:39:32

#include <bits/stdc++.h>
#define speed cin.tie(0)->sync_with_stdio(0)
#define ll long long
#define pii pair<int,int>
using namespace std;

int main(){
	speed;
	ll n;cin >> n;
	ll temp=((n*n)+n)/2;
	ll idx=n*3/4;ll mn=min(idx+2,n);
	ll realmn=((idx*idx)+idx)/2;temp-=realmn;
	//cout << idx << " ";
	cout << abs(temp-realmn);
	return 0;
}