#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
// My bug list :
// integer overflow
// 0based, 1based forgotten
// index out of bound
// n, m, i, j typo
// some cases are missing

const int MAX_N = 3010, inf = 1e9;

int need(vector<tuple<int,int,int>> lhs) {
    sort(AI(lhs));
    //     r, x
    priority_queue<pair<int,int>, vector<pair<int,int>>, greater<pair<int,int>>> pq;
    int lst = -1;
    for (auto [l, r, x] : lhs) {
        int d = l - lst;
        while (pq.size() && d) {
            auto [r, x] = pq.top(); pq.pop();
            int v = min(x, d);
            x -= v, d -= v;
            lst += v;
            if (x > 0) pq.emplace(r, x);
        }
        pq.emplace(r, x);
        lst = l;
    }
    while (pq.size()) {
        auto [r, x] = pq.top(); pq.pop();
        if (lst+x-1 > r) return false;
        lst += x;
    }
    return true;
}

vector<tuple<int,int,int>> operator + (vector<tuple<int,int,int>> t, tuple<int,int,int> v) { t.pb(v); return t; }

int32_t main() {
    ios_base::sync_with_stdio(0), cin.tie(0);
    int n;
    cin >> n;
    vector<tuple<int,int,int,int>> seg(n);
    for (auto &[p, l, r, x] : seg)
        cin >> l >> r >> x >> p;

    vector<tuple<int,int,int>> vset;

    ll res = 0;

    sort(AI(seg), greater<>());

    for (auto [p, l, r, x] : seg) {
        int lo = 0, hi = x, mid;
        while (lo < hi) {
            mid = lo + hi >> 1;
            if (valid(vset + make_tuple(l, r, mid+1)))
                lo = mid+1;
            else
                hi = mid;
        }
        ll c = lo;
        assert(c <= x);
        res += c * p;
        if (c) {
            vset.pb(l, r, c);
        }
    }

    cout << res << '\n';
}