#include <bits/stdc++.h>
#define int long long
#define ll long long
#define pb push_back
#define fi first
#define se second
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<char,char> pcc;
typedef pair<pii,int> ipii;
typedef pair<pii,pii> ipiii;
const int MAXN = 2e5+10;
const int MAXA = 1e7+10;
const int INF = 1e18+10;
const int SQRT = 300;
const int LOG = 20;
const ld EPS = 1e-6;
const int MOD = 998244353;
int sum(int a, int b){ return (a+b)%MOD; }
void chsum(int &a, int b){ a = (a+b)%MOD; }
void chsub(int &a, int b){ a = (a+MOD-b)%MOD; }
int mul(int a, int b){ return (a*b)%MOD; }
void chmul(int &a, int b){ a = (a*b)%MOD; }
void chmn(int &a, int b){ a = min(a, b); }
void chmx(int &a, int b){ a = max(a, b); }
int n, m, x[MAXN], y[MAXN];
int ans = INF;
void cek(int siz){
int bl = 0, wh = 0;
for(int i=1; i<=m; i++){
int row = x[i]/siz, col = y[i]/siz;
if((row+col)%2 == 0) bl++;
else wh++;
}
int blcell = ((n/siz)*(n/siz)+1)/2; blcell *= siz*siz;
int whcell = (n/siz)*(n/siz)/2; whcell *= siz*siz;
chmn(ans, blcell -bl+wh);
chmn(ans, whcell -wh+bl);
}
signed main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>n>>m;
for(int i=1; i<=m; i++){
int a,b; cin>>a>>b;
cin>>x[i]>>y[i]; x[i]--; y[i]--;
}
for(int siz=1; siz*siz<=n; siz++){
if(n%siz==0){
cek(siz);
if(siz!=1 && siz*siz!=n) cek(n/siz);
}
}
cout << ans << '\n';
}
