#include<bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define pb push_back
#define ll long long
const int N = 1e5 + 5;
const ll inf = 1e18;
long long n, k, x[N], y[N], cnt1, cnt2, m1, m2, ans = inf, b1, b2, s;
vector<long long> v;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> k;
for(ll i = 1; i * i <= n; ++i){
if(n % i == 0){
v.pb(i);
if(i != n / i) v.pb(n / i);
}
}
for(ll i = 1, x1, y1; i <= k; ++i){
cin >> x[i] >> y[i];
cin >> x1 >> y1;
}
for(auto to : v){
if(to == n) continue;
cnt1 = 0;
cnt2 = 0;
for(ll i = 1; i <= k; ++i){
b1 = (x[i] + to - 1) / to;
b2 = (y[i] + to - 1) / to;
if(b1 % 2) {
if(b2 % 2) cnt1++;
else cnt2++;
}
else {
if(b2 % 2) cnt2++;
else cnt1++;
}
}
// cout << to << ' ' << cnt1 << ' ' << cnt2 << '\n';
s = n / to;
// cout << s << '\n';
m1 = (s + 1) / 2 * ((s + 1) / 2) + (s / 2) * (s / 2);
m2 = s * s - m1;
// cout << m1 << ' ' << m2 << '\n';
m1 *= to * to;
m2 *= to * to;
// cout << m1 << ' ' << m2 << '\n';
ans = min(ans, min(m1 - cnt1 + cnt2, m2 - cnt2 + cnt1));
// cout << m1 - cnt1 + cnt2 << '\n' << m2 - cnt2 + cnt1 << '\n';
}
cout << ans;
return 0;
}
