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

#define endl '\n'
using ll = long long;

const int N = 2e5 + 10;

int n;

void solve () {
    cin >> n;
    multiset<int> stl, str;
    for (int i = 1; i <= n; i ++) {
        char opt;
        int l, r;
        cin >> opt >> l >> r;
        if (opt == '+') {
            stl.insert(l);
            str.insert(r);
        }
        else {
            stl.erase(stl.find(l));
            str.erase(str.find(r));
        }
        if (stl.empty()) {
            cout << "NO\n";
            continue;
        }
        if (*stl.rbegin() > *str.begin()) cout << "YES\n";
        else cout << "NO\n";
    }
}

signed main () {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int _ = 1;
//  cin >> _;
    while (_ --) {
        solve();
    }

    return 0;
}