/*
AUTHOR : BELGIANBOT
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> void read(T& x) { cin >> x;}
template<typename T1, typename T2> void read(pair<T1, T2>& p) { read(p.first), read(p.second);}
template<typename T> void read(vector<T>& v) { for (auto& x : v) read(x); }
template<typename T1, typename T2> void read(T1& x, T2& y) { read(x), read(y); }
template<typename T1, typename T2, typename T3> void read(T1& x, T2& y, T3& z) { read(x), read(y), read(z); }
template<typename T1, typename T2, typename T3, typename T4> void read(T1& x, T2& y, T3& z, T4& zz) { read(x), read(y), read(z), read(zz); }
template<typename T> void print(vector<T>& v) { for (auto& x : v) cout << x << ' '; cout << endl; }
#define quit(x) return (void)(cout << x << endl)
#define pb push_back
#define fi first
#define se second
#define ordered_set tree<pair<int,int>, null_type, less<pair<int,int>>, rb_tree_tag, tree_order_statistics_node_update>
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define mp make_pair
#define sz(x) (int)(x.size())
#define YES cout<<"YES\n"
#define NO cout<<"NO\n"
#define QYES quit("YES")
#define QNO quit("NO")
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)
#define int long long
#define double long double
const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=20;
void solve();
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
int t = 1;
//cin >> t;
while (t--) solve();
return 0;
}
int k, n, m, p, q;
const int N = 300000;
vector<vector<int>> adj;
vector<int> t;
vector<pair<int,int>> state;
void build() {
for (int i = n-1; i>0; i--) t[i] = min(t[i<<1],t[i<<1|1]);
}
void update(int pos, int value) {
t[pos+=n] = value;
for (int i = pos >> 1; i > 0; i >>= 1) t[i] = min(t[i<<1],t[i<<1|1]);
}
int query(int l, int r) {
int res = inf;
for (l += n, r += n+1; l < r; l >>= 1, r >>= 1) {
if (l&1) res = min(res, t[l++]);
if (r&1) res = min(res, t[--r]);
}
return res;
}
void solve() {
cin >> n;
t.resize(4 * n, inf);
state.resize(n);
multiset<pair<int,int>> st;
for (int i = 0; i < n; i++) {
int a; cin >> a;
if (a > 0) {
state[i] = {a,i};
update(i, 0);
st.insert({i,a});
}
else {
a = -a;
int l = 0, r = i, res = 0;
while (l <= r) {
int mid = (r + l) / 2;
int q = query(mid, r);
if (q < a) {
res = mid;
l = mid+1;
}
else r = mid-1;
}
state[i] = state[res];
update(i, a);
if (!query(res, res)) st.erase(st.lower_bound({res, -1}));
else {
update(state[i].se, 0);
st.insert({state[i].se, state[i].fi});
}
update(res, inf);
}
cout << (st.empty() ?0: (--st.end())->second) << '\n';
}
}
