// Jan Kanty Milczek
#include <cstdio>
int max(int x, int y) {
if (x > y)
return x;
else
return y;
}
int max(int x, int y, int z) {
return max(x, max(y, z));
}
struct PersTree {
PersTree *l, *r;
int key;
int value;
int max_value;
int find(int) const;
PersTree *add(int, int) const;
PersTree(PersTree *_l, PersTree *_r, int _key, int _value, int _max_value) : l(_l), r(_r), key(_key), value(_value), max_value(_max_value) {}
};
int safe_max_value(PersTree *x) {
if (x == NULL)
return 0;
return x->max_value;
}
int PersTree::find(int mxkey) const {
if (mxkey < key)
return l->find(mxkey);
else if (mxkey == key)
return max(safe_max_value(l), value);
else // if (mxkey > key)
return max(safe_max_value(l), value, r->find(mxkey));
}
PersTree *PersTree::add(int _key, int nvalue) const {
PersTree *_l = l;
PersTree *_r = r;
int _value = value;
if (_key < key)
_l = l->add(_key, nvalue);
else if (_key == key)
_value = nvalue;
else // if (_key > key)
_r = r->add(_key, nvalue);
return new PersTree(_l, _r, key, _value, max(safe_max_value(_l), _value, safe_max_value(_r)));
}
PersTree *create_pers_tree(int left, int right) {
if (left > right)
return NULL;
int s = (left + right) / 2;
return new PersTree(create_pers_tree(left, s - 1), create_pers_tree(s + 1, right), s, 0, 0);
}
int n;
const int M = 3e5 + 5;
PersTree *akt[M];
int wyn[M];
int main() {
scanf("%d", &n);
akt[0] = create_pers_tree(0, n);
wyn[0] = 0;
for (int i = 1; i <= n; ++i) {
int op;
scanf("%d", &op);
if (op > 0) {
wyn[i] = op;
akt[i] = akt[i-1]->add(0, i);
} else {
int cof = akt[i-1]->find(-op-1) - 1;
wyn[i] = wyn[cof];
akt[i] = akt[cof]->add(-op, i);
}
printf("%d\n", wyn[i]);
}
}
