#include <bits/stdc++.h>
#define IO_OP std::ios::sync_with_stdio(0); std::cin.tie(0);
#define F first
#define S second
#define V vector
#define PB push_back
#define MP make_pair
#define EB emplace_back
#define ALL(v) (v).begin(), (v).end()
#define debug(x) cerr << "Line(" << __LINE__ << ") -> " << #x << " is " << x << endl
using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;
const int INF = 1e9 + 7;
const ll oo = 1e18;
signed main()
{
IO_OP;
int n, k;
cin >> n >> k;
V<array<int, 4>> a(k);
for(int i = 0; i < k; i++) {
for(int j = 0; j < 4; j++)
cin >> a[i][j], a[i][j]--;
}
ll ans = oo;
auto go = [&] (int b) {
assert(n % b == 0);
int m = n / b;
ll black = (ll) m * m / 2 * b * b, white = (ll) n * ns- black;
int black_type = 1;
for(int _ = 0; _ < 2; _++) {
int in_black = 0, in_white = 0;
for(int i = 0; i < k; i++) {
int tt = a[i][0] / b + a[i][1] / b;
if(tt % 2 == black_type) in_black++;
else in_white++;
}
assert(in_black <= black);
assert(in_white <= white);
ans = min(ans, in_white + black - in_black);
swap(black, white);
black_type ^= 1;
}
};
for(int i = 1; i * i <= n; i++) {
if(n % i == 0) {
go(i);
if(n / i != i && n / i != n) go(n / i);
}
}
cout << ans << '\n';
}
Compilation message
chessboard.cpp: In lambda function:
chessboard.cpp:37:55: error: 'ns' was not declared in this scope; did you mean 'ans'?
37 | ll black = (ll) m * m / 2 * b * b, white = (ll) n * ns- black;
| ^~
| ans
