Submission #942931

#	Time	Username	Problem	Language	Result	Execution time	Memory
942931		Teemka	Chessboard (IZhO18_chessboard)	C++17	39 / 100	60 ms	3800 KiB

chessboard

#include "bits/stdc++.h" 
#define F first
#define S second
#define ALL(a) a.begin() , a.end()

#ifndef ONLINE_JUDGE
#define OK  cout << __LINE__ << "| "<< "---------------------------OK-----------------------" << endl;
#define deb(x) cout << __LINE__ << "| "<< #x  << " = " << x << endl;
#else
#define OK  
#define deb(x) 
#endif
 
typedef long double ld;
typedef long long ll;
using namespace std ;
const ll N = 1e3 + 7 ;	
const ll INF = 1e9;
const ll mod = 1e9 + 7 ;
const double eps = 1e-9 ;
const int dx[]  = { 0 , 0 , 1 , -1, 1 , -1 , 1 , -1} , dy[] = {1 , -1 , 0 , 0 , 1 , 1, -1 , -1}  ;
int n, k;
struct query{
	int x1, x2 ,y1 ,y2;
	query(int _x1, int _x2 ,int _y1, int _y2){
		x1 = _x2, x2 = _x2, y1 = _y1, y2 = _y2;
	}
};
vector<query> vec;
void test_solve(int test_index){
	cin >> n >> k;
	for(int i = 1; i <= k; i++){
		int x1, x2, y1, y2;
		cin >> x1 >> y1 >> x2 >> y2;
		vec.push_back(query(x1 , x2 ,y1 ,y2));
	}
	int ans = INF;
	for(int i = 1; i < n; i++){
		if(n % i)
			continue;
		int cnt[2] = {0 , 0};
		for(auto [x1 ,x2 ,y1, y2] : vec){
			int dnt[2] = {0 , 0};
			for(int j = x1; j <= x2; j++){
				if((j - 1) / i % 2){
					dnt[1]++;
				}	
				else{
					dnt[0]++;
				}
			}
			for(int j = y1; j <= y2; j++){
				if((j - 1) / i % 2){
					cnt[1] += dnt[0];
					cnt[0] += dnt[1];
				}
				else{
					cnt[0] += dnt[0];
					cnt[1] += dnt[1];
				}
			}
		}
		int d = n / i , less , big;
		if(d % 2){
			less = (d * d - 1) / 2 * (i * i);
			big = less + i * i;
		}
		else{
			less = (d * d) / 2 * (i * i);
			big = less;
		}
		// deb(big);
		// deb(less);
		// deb(cnt[0]);
		// deb(cnt[1]);
		// deb(i);
		ans = min({ans, (big - cnt[0]) + cnt[1] , cnt[0] + (less- cnt[1])});
	}
	cout << ans << endl;
}

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