#include <bits/stdc++.h>
using namespace std;

#define F first
#define S second 
#define mp make_pair
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define speed ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define sz(x) (int)x.size()
#define len(x) (int)strlen(x)
#define all(x) x.begin(), x.end()
#define debug cerr << "OK\n";
#define ub upper_bound
#define lb lower_bound 
#define make_unique(x) sort(all(x)), x.erase(unique(all(x)), x.end())

mt19937 bruh(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rofl(chrono::steady_clock::now().time_since_epoch().count());

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef set<int> si;
typedef set<ll> sll;
typedef set<pii> spii;
typedef set<pll> spll;
typedef multiset <int> msi;
typedef multiset <ll> msll;
typedef map <int, int> mi;
typedef map <ll, ll> mll;

const int N = 1e6 + 2;
const int M = 1e5;
const int mod = 0;
const int inf = 2e9 + 3;
const ll INF = 1e18;
const ld pi2 = 2.0 * 3.141592653589793;
const ld pi = 3.141592653589793;
const ld eps = 1e-12;

const int dx[4] = {1, -1, 0, 0};
const int dy[4] = {0, 0, -1, 1};

#ifndef PC
    #define gcd __gcd
#endif

void files(string s = "main") {
    #ifndef PC
        freopen((s + ".in").c_str(), "r", stdin);
        freopen((s + ".out").c_str(), "w", stdout);
    #endif
}

int add(int a, int b) {
    if (a + b < 0) return a + b + mod;
    if (a + b >= mod) return a + b - mod;
    return a + b;		
}

int mul(int a, int b) {
    return a * 1LL * b % mod;
}

int binpow(int a, int n) {
    int ret = 1;
    while (n) {
        if (n & 1) ret = mul(ret, a);
        a = mul(a, a);
        n >>= 1;
    }
    return ret;
}

int n, m, u[N], was[N];
ll A, B, a[N], b[N];
pii anc[N];
vpii g[N];
vector<vpii> vec;

void dfs(int v, int p = 0) {
    u[v] = -1;
    for (auto [to, id] : g[v]) {
        if (to == p) continue;
        if (u[to] == 0) {
            anc[to] = {v, id};
            dfs(to, v);
        }
        else if (was[id] == 0) {
            int k = v;
            vec.pb({});
            while (true) {
                vec.back().pb({a[anc[k].S], b[anc[k].S]});
                u[k] = v;
                k = anc[k].F;
                if (k == to) break;
            }
            was[id] = 1;
            vec.back().pb({a[id], b[id]});
        }
    }
}

int sign(ll x) {
    if (x == 0) return 0;
    return x / abs(x);
}

pii add(pii v, pii u) {
    v.F += u.F, v.S += u.S;
    return v;
}

pii sub(pii v, pii u) {
    v.F -= u.F, v.S -= u.S;
    return v;
}

int prod(pii v, pii u) {
    return sign(v.F * u.S - v.S * u.F);
}

int dot(pii v, pii u) {
    return sign(v.F * v.S + u.F * u.S);
}

int pos(pii p) {
    if (p.F > 0) return 0;
    if (p.F < 0) return 1;
    if (p.S >= 0) return 0;
    return 1;
}

bool cmp(pii v, pii u) {
    if (pos(v) != pos(u)) return pos(v) < pos(u);
    return prod(u, v) >= 0;
}

vpii convex(vpii v) {
    sort(all(v));
    vpii c;
    c.pb({0, 0});
    for (auto p : v) {
        while (sz(c) > 1 && prod(sub(c[sz(c) - 1], c[sz(c) - 2]), sub(p, c[sz(c) - 2])) >= 0) {
            c.ppb();
        }
        c.pb(p);
    }
    vpii r;
    for (int i = 0; i < sz(c); ++i) {
        r.pb(sub(c[(i + 1) % sz(c)], c[i]));
    }
    return r;
}

int main() {
    speed;
    cin >> n >> m;
    for (int i = 1, v, u; i <= m; ++i) {
        cin >> v >> u >> a[i] >> b[i];
        A += a[i], B += b[i];
        g[v].pb({u, i});
        g[u].pb({v, i});
    }
    dfs(1);
    vpii V;
    for (auto &v : vec) {
        for (auto p : convex(v))
            V.pb(p);
    }
    sort(all(V), cmp);
    pii P = {0, 0};
    ll ans = A * B;
    for (auto p : V) {
        P = add(P, p);
        ans = min(ans, (A - P.F) * (B - P.S));
    }
    cout << ans << '\n';

    


}