Submission #68097

#	Time	Username	Problem	Language	Result	Execution time	Memory
68097		MatheusLealV	Chessboard (IZhO18_chessboard)	C++17	70 / 100	561 ms	60864 KiB

chessboard

#include <bits/stdc++.h>
#define N 100050
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;

ll n, k, x[N], y[N], xf[N], yf[N];

long long ans = (2000000000000000000ll);

vector<ll> d;

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

	cin>>n>>k;

	for(int i = 1; i <= k; i++) cin>>x[i]>>y[i]>>xf[i]>>yf[i];

	for(int i = 1; i <= k; i++) x[i] --, y[i] --, xf[i] --, yf[i] --;

	for(int i = 1; i <= sqrt(n); i++)
	{
		if((n % i) != 0) continue;

		d.push_back(i);

		if(i != n/i) d.push_back(n/i);
	}

	for(auto r: d)
	{	
		ll pretocerto = 0, pretoerrado = 0, tot;

		if(r == n) continue;

		tot = ( ((n/r) * (n/r)) + 1LL)/2LL;

		tot = (tot * r * r); 

		//if(r != 2) continue;

		for(int i = 1; i <= k; i++)
		{
			int linha = (x[i] % (2*r) < r ? 1 : 0), coluna = (y[i] % (2*r) < r ? 1 : 0);

			if(!linha) coluna = !coluna;

			if(!coluna) pretoerrado ++;

			else pretocerto ++;
		}

		//cout<<custo<<" "<<branco<<"\n";

		ans = min(ans, tot - pretocerto + pretoerrado);

		tot = ( ((n/r) * (n/r)))/2LL;

		tot = (tot * r * r); 

		ans = min(ans, tot + pretocerto - pretoerrado);

	}

	cout<<ans<<"\n";
}

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 15 / 15
• Subtask 4: 16 / 16
• Subtask 5: 23 / 23
• Subtask 6: 0 / 30