Submission #488078

#	Time	Username	Problem	Language	Result	Execution time	Memory
488078		nickmet2004	Chessboard (IZhO18_chessboard)	C++11	70 / 100	197 ms	5704 KiB

chessboard

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N= 1e5 + 5;
int n , k;
int A[N] , B[N] , C[N] , D[N];
int cnt[2];
int ans = 1e18;
void q(int x){
    int sz = n / x;
    for(int i = 0; i < k; ++i){
        cnt[(B[i] /x + A[i] / x) % 2]++;
    }
    int bk = ((n*n / (x * x)) / 2) * x * x ,ok = 0;
    if(sz % 2 == 1) ok = 1;
    int Y = bk - cnt[1] + cnt[0];
    ans = min(ans , Y);
    bk = (((n * n) / (x * x)) - ((n*n / (x * x)) / 2)) * x * x;
    Y = bk - cnt[0] + cnt[1];
    ans = min(ans, Y);
    cnt[0]=cnt[1]=0;
    //cout << endl;
}
 main (){
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> k;
    for(int i = 0; i < k; ++i){
        cin >> A[i] >> B[i] >> C[i] >> D[i];
        --A[i] , --B[i] , --C[i] , --D[i];
    }//cout << endl;
    for(int i = 1; i * i <=n; ++i){
        if(n % i ==0){
            if((n / i) != n)q(n/i);
            if((n/i) != i)q(i);
        }
    }
    cout << ans;
}

Compilation message (stderr)

chessboard.cpp: In function 'void q(long long int)':
chessboard.cpp:14:45: warning: variable 'ok' set but not used [-Wunused-but-set-variable]
   14 |     int bk = ((n*n / (x * x)) / 2) * x * x ,ok = 0;
      |                                             ^~
chessboard.cpp: At global scope:
chessboard.cpp:24:2: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   24 |  main (){
      |  ^~~~

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