Submission #334338

#	Time	Username	Problem	Language	Result	Execution time	Memory
334338		amunduzbaev	Chessboard (IZhO18_chessboard)	C++14	8 / 100	2 ms	620 KiB

chessboard

#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long 
#define ld long double 
#define pii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define prc(n) fixed << setprecision(n)
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pi acos(-1);
const int inf = 1e9+7;
const int N = 1e3+5;

vector<pii>v;
int x[N][N];
ll ans, n, k;

void check(int rem){
	int cnt = 0;
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			if((j + i)%2 == rem && !x[i][j]) cnt++;
			else if((i+j) % 2 != rem && x[i][j]) cnt++;
		}
	}
	ans = min((ll)cnt, ans);
}

void solve(){
	fastios
	ans = inf;
	cin>>n>>k;
	if(k == 0){
		ans = n*n/2;
		for(int i=2;i*1ll*i<=n;i++){
			if(n % i == 0){
				ll num = n/i;
				ans = min(ans, num * num /2 * i * i);
				num = i;
				ans = min(ans, num * num /2 * (n/i) * (n/i));
			}
		}
		cout<<ans<<"\n";
		return;
	}
	for(int i=0;i<k;i++){
		int a, b, c, d;
		cin>>a>>b>>c>>d;
		x[--a][--b] = 1;
	}
	
	check(1);
	check(0);
	cout<<ans;
	return;
}
/*

3 3
1 3 1 3
2 3 3 3
1 1 3 1

5 8
2 1 2 1
3 1 3 1
5 2 5 2
1 5 1 5
2 3 2 3
2 4 2 4
3 3 3 3
4 3 4 3

*/
int main(){
	fastios
	int t = 1;
	//cin>>t;
	while(t--) solve();
	return 0;
}

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