#include <bits/stdc++.h>
#define pb push_back
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define all(data) data.begin() , data.end()
#define endl '\n'
//freopen("nenokku_easy.in", "r", stdin);
//freopen("nenokku_easy.out", "w", stdout);
//#define int long long
using namespace std;
typedef long long ll;
const int N = 1e3 + 5;
int n, k, y[N], x[N];
long long pref[N][N];
main() {
/*ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);*/
cin >> n >> k;
for(int kk = 1; kk <= k; kk++) {
int xx, yy;
cin >> x[kk] >> y[kk] >> xx >> yy;
pref[x[kk]][y[kk]] = 1;
}
if(k == 0) {
cout << n * n / 2;
return 0;
}
vector < int > dv;
dv.pb(1);
for(int i = 2; i <= sqrt(n); i++) {
if(n % i == 0) {
dv.pb(i);
if(n / i != i) dv.pb(n / i);
}
}
sort(all(dv));
if(dv.size() == 1) {
int odd = 0, even = 0;
for(int i = 1; i <= k; i++) {
if(x[i] % 2 == y[i] % 2) odd++;
else even++;
}
cout << (n * n + 1) / 2 - max(even, odd) + min(even, odd);
return 0;
}
for(int i = 1; i <= n; i++) {
for(int j = 1; j <= n; j++) {
pref[i][j] += pref[i - 1][j] + pref[i][j - 1] - pref[i - 1][j - 1];
//cout << pref[i][j] << " ";
}
//cout << endl;
}
long long ans = n * n * n;
for(int v = 0; v < dv.size(); v++) {
int z = dv[v];
int type = 1;
long long res1 = 0, res2 = 0;
for(int i = z; i <= n; i += z) {
if(i > n) break;
for(int j = z; j <= n; j += z) {
if(j > n) break;
if(type) {
res1 += pref[i][j] - pref[i][j - z] - pref[i - z][j] + pref[i - z][j - z];
res2 += z * z - (pref[i][j] - pref[i][j - z] - pref[i - z][j] + pref[i - z][j - z]);
} else {
res1 += z * z - (pref[i][j] - pref[i][j - z] - pref[i - z][j] + pref[i - z][j - z]);
res2 += pref[i][j] - pref[i][j - z] - pref[i - z][j] + pref[i - z][j - z];
}
type = 1 - type;
}
}
ans = min(ans, min(res1, res2));
}
cout << ans;
}
/*
5
2 8 5 1 10
5
2 3 5 3
2 5 3 3
1 4 4
2 3 4 2
1 1 2
*/
Compilation message
chessboard.cpp:18:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
18 | main() {
| ^~~~
chessboard.cpp: In function 'int main()':
chessboard.cpp:58:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
58 | for(int v = 0; v < dv.size(); v++) {
| ~~^~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
0 ms |
204 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
332 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
588 KB |
Output is correct |
2 |
Correct |
1 ms |
588 KB |
Output is correct |
3 |
Correct |
1 ms |
588 KB |
Output is correct |
4 |
Correct |
1 ms |
588 KB |
Output is correct |
5 |
Correct |
1 ms |
588 KB |
Output is correct |
6 |
Incorrect |
1 ms |
588 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
588 KB |
Output is correct |
2 |
Correct |
1 ms |
588 KB |
Output is correct |
3 |
Correct |
1 ms |
588 KB |
Output is correct |
4 |
Correct |
1 ms |
588 KB |
Output is correct |
5 |
Correct |
1 ms |
588 KB |
Output is correct |
6 |
Incorrect |
1 ms |
588 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
332 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
0 ms |
204 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |