Submission #290540

#	Time	Username	Problem	Language	Result	Execution time	Memory
290540		matheo_apd	Chessboard (IZhO18_chessboard)	C++17	8 / 100	149 ms	3832 KiB

chessboard

#include <bits/stdc++.h>
using namespace std;
#define maxn 100005
#define ll long long int
ll n, k;
vector<int> chess[maxn];
void solve_k0(){
	ll minimo = 999999;
	for(int i = 1; i < n; i++){
		if(n % i != 0) continue;
		int test = i*i;
		minimo = min(minimo, ((n*n/test)/2)*test);
	}
	cout << minimo << endl;
}
ll block(ll number, ll siz){
	return ((n-1)/siz + 1)%2;
}
ll solve_square(ll siz){
	ll cont = 0;
	for(int i = 1; i <= n; i++){
		ll cont_errado = 0, cont_certo = 0;
		for(int j = 0; j < chess[i].size(); j++){
			//if((i+j)%2 == chess[i][j]) cont_errado++;
			int row = chess[i][j];
			if(block(i, siz) == block(row, siz)) cont_certo++;
			else cont_errado++;
		}
		cont += cont_errado	+ n/2 + block(i, siz) - cont_certo;
	}
	return min(cont, n*n - cont);
}
int main(){
	memset(chess, 0, sizeof chess);
	cin >> n >> k;
	if(k == 0) solve_k0();
	else{
		for(int i = 0; i < k; i++){
			int x, y, l, m;
			cin >> x >> y;
			cin >> l >> m; //8)
			chess[x].push_back(y);
		}
		ll minimo = 999999999999;
		for(ll i = 1; i < n; i++){
			if(i%n) minimo = min(minimo, solve_square(i));
		}
	}
	return 0;
}

Compilation message (stderr)

chessboard.cpp: In function 'long long int solve_square(long long int)':
chessboard.cpp:23:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |   for(int j = 0; j < chess[i].size(); j++){
      |                  ~~^~~~~~~~~~~~~~~~~

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