Submission #495037

#	Time	Username	Problem	Language	Result	Execution time	Memory
495037		pragmatist	Chessboard (IZhO18_chessboard)	C++17	39 / 100	68 ms	2876 KiB

chessboard

#include <bits/stdc++.h>                            
 
#define pb push_back
#define sz(v) (int)v.size()
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define x first
#define y second
#define int long long
#define nl "\n"
 
using namespace std;

typedef long long ll;
typedef pair<long long, long long> pll;
typedef pair <ll, ll> pii;

const int N = (int)3e5 + 7;
const int M = (int)7e6 + 7;
const ll MOD = (ll)1e9 + 7;                    
const int inf = (int)1e9 + 7;
const ll INF = (ll)3e18 + 7;

pii dir[] = {{-1, -1}, {1, 1}, {-1, 1}, {1, -1}};

int n, k;
bool c[1001][1001];

int f(int x, bool cur) {
    int ans = 0;
	for(int i = 1; i <= n; i += x) {
	    bool ok = cur;
	    for(int j = 1; j <= n; j += x) {
	    	int k = j + x - 1, t = i + x - 1;
	    	for(int l = i; l <= t; ++l) {
	    		for(int r = j; r <= k; ++r) {
	    			if(ok) ans += (c[l][r] == 0);
	    			else ans += (c[l][r] == 1);
	    		}
	    	}
	    	ok ^= 1;
	    }
		cur ^= 1;
	}
	return ans;
}

void solve() {          	             
	cin >> n >> k;
	while(k--) {
		int x1, y1, x2, y2;
		cin >> x1 >> y1 >> x2 >> y2;
		for(int i = x1; i <= x2; ++i) {
			for(int j = y1; j <= y2; ++j) {
				c[i][j] = 1;
			}
		}
	}
	int ans = inf;
	for(int i = 1; i < n; ++i) {
		if(n % i == 0) {
			ans = min(ans, f(i, 0));
			ans = min(ans, f(i, 1));			
		}
	}
	cout << ans << nl;
}

signed main() {                   
	ios_base::sync_with_stdio(NULL);
    cin.tie(0);
    cout.tie(0);
   	int test = 1;
	//cin >> test;
	for(int i = 1; i <= test; ++i) {
        //cout << "Case " << i << ": ";
        solve();
    }
    return 0;
}

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