#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
using ll = long long;
using ii = pair<int, int>;
const int MX = 1e5+5;

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int N; cin >> N;
	vector<pair<ii, int>> A, C;
	for (int i = 0; i < N; ++i) {
		int q, t, x, n; cin >> q >> t >> x >> n;
		if (q == 1) C.emplace_back(ii(t+x, t-x), n);
		else A.emplace_back(ii(t+x, t-x), n);
	}
	sort(begin(A), end(A), [](auto & a, auto & b) { return a.f.s < b.f.s; });
	sort(begin(C), end(C), [](auto & a, auto & b) { return a.f.s < b.f.s; });
	set<pair<ii, int>> S;
	int i = 0, ans = 0;
	for (auto & a : A) {
		while (i < C.size() && C[i].f.s <= a.f.s) S.insert(C[i++]);
		int n = a.s;
		while (n > 0 && S.size() && begin(S)->f.f <= a.f.f) {
			auto c = *prev(S.upper_bound({ii(a.f.f, 1e9), 0}));
			S.erase(c);
			int x = min(n, c.s);
			ans += x, n -= x;
			if (x < c.s) S.emplace(c.f, c.s-x);
		}
	}
	cout << ans;
}