제출 #342861

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
342861		Rakhmand	Chessboard (IZhO18_chessboard)	C++14	39 / 100	335 ms	2924 KiB

chessboard

//
//  main.cpp
//  torelax
//
//  Created by Rakhman on 11/15/20.
//

#include <cstring>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <queue>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cassert>
#include <iterator>

#define ios ios_base::sync_with_stdio(0), cout.tie(0), cin.tie(0);
#define S second
#define F first
#define pb push_back
#define nl '\n'
#define NL cout << '\n';
#define EX exit(0)
#define all(s) s.begin(), s.end()
#define no_answer {cout << "NO"; exit(0);}
#define FOR(i, start, finish, k) for(llong i = start; i <= finish; i += k)

const long long mxn = 2e6 + 110;
const long long mnn = 1e3 + 2;
const long long mod = 1e9 + 7;
const long long inf = 1e18;
const long long OO = 1e9;

typedef long long llong;
typedef unsigned long long ullong;

using namespace std;

int n, k;
llong ans = inf;
bool black[mnn][mnn];

struct dot{
    int left, up, right, down;
}b[mxn];

llong get_color(int x, int y, int d){
    return (((x - 1) / d) + ((y - 1) / d)) % 2;
}

llong get(llong x){
    llong cnt = 0;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            cnt += (get_color(i, j, x) == black[i][j]);
        }
    }
    llong cnt1 = 0;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= n; j++){
            cnt1 += (get_color(i, j, x) != black[i][j]);
        }
    }
    return min(cnt1, cnt);
}

int main() {
    ios;
    cin >> n >> k;
    for(int i = 1; i <= k; i++){
        cin >> b[i].left >> b[i].up >> b[i].right >> b[i].down;
        black[b[i].left][b[i].up] = true;
    }
    for(int i = 1; i <= sqrt(n); i++){
        if(n % i == 0){
            ans = min(ans, get(i));
            //cout << i << ' ' << ans << nl;
            if(n / i != i && i != 1){
                ans = min(get(n / i), ans);
                //cout << n / i << ' ' << ans << nl;
            }
        }
    }
    cout << ans;
}


/*
 6 8
 3 3 3 3
 1 2 1 2
 3 4 3 4
 5 5 5 5
 4 3 4 3
 4 4 4 4
 2 1 2 1
 3 6 3 6
 
 */

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