#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define in insert
#define lb lower_bound
#define F first
#define S second
#define sz size()
#define int long long
#define all(v) v.begin(),v.end()
#define FOR1(x, n) for(int j = x; j <= n; j ++)
#define FOR(x, n, m, d) for(int x = n; x <= m; x += d)
#define FORR(x, n, m, d) for(int x = n; x >= m; x -= d)
#define nikita ios_base::sync_with_stdio(0), cin.tie(0);
const int N = 1e6+5;
int b[N], a[N];
int n,m,k,sum=0,x,y, ans, r,pref[N], cnt, l, mod = 1e9+7, cal,lp = 1;
void solve(){
cin >> n >> m;
vector<int>v;
k = n/2;
FOR(i, 1, k, 1){
if(n%i==0)v.pb(i);
}
FOR(i, 0, v.sz-1, 1){
k = n / v[i];
if(k%2==0)b[i] = (k/2) * v[i] * v[i] * k;
else{
b[i] = ((k+1)/2) * v[i] * v[i] * ((k+1)/2);
b[i] += (k/2) * v[i]*v[i] * (k/2);
}
}
FOR(i, 1, m, 1){
int x1, y1, x2, y2;
cin >> x1 >> y1 >> x2 >> y2;
x1--,y1--, x2--, y2--;
FOR(j, 0, v.sz-1, 1){
bool f = 0;
int ini = b[j];
x = x1 / v[j], y = y1 / v[j];
if((x+1)*v[j] <= x2)
{
k = (x+1)*v[j] - x1;
if( x % 2 == y % 2 ) b[j] -= k;
else b[j] += k, f = 1;
sum = x2 - x1 + 1 - k;
if( ( sum / v[j] ) % 2 ){
if(f)b[j] -= k;
else b[j] += k;
f ^= 1;
}
sum %= v[j];
if(!f)b[j] += sum;
else b[j] -= sum;
}
else{
b[j] -= (x2-x1+1) * (x%2==y%2 ? 1 : -1);
}
int lp = (ini - b[j]) * -1;
b[j] = ini;
f = 0;
if((y+1)*v[j] <= y2 ){
sum = (y+1)*v[j] - y1;
b[j] += sum * lp;
int obshi = y2 - y1 + 1 - sum;
if( (obshi / v[j]) % 2 )b[j] -= v[j] * lp, f = 1;
obshi %= v[j];
b[j] -= obshi * lp * (f != 1 ? 1 : -1);
}
else{
b[j] += (y2-y1+1) * lp;
}
}
}
ans = 1e18;
FOR(j, 0, v.sz-1, 1){
if(b[j])ans = min({ans, b[j], n*n-b[j]});
}
cout << ans;
}
signed main(){
nikita
int tt = 1;
if(!tt)cin >> tt;
FOR(i, 1, tt, 1)solve();
}
