#include <bits/stdc++.h>
using namespace std;
const int mxN = 3e5+5;
int p[mxN][20];
int l[mxN];
int v[mxN];
int getp(int i, int t){
//first parent of i with level < t
while (l[i] >= t){
for (int j = 1; j < 20; j++){
if (l[p[i][j]] < t){ i = p[i][j-1]; break;}
}
}
return i;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
cin >> n;
l[0] = -1;
memset(p,0,sizeof(p));
int c;
for (int i = 1; i <= n; i++){
cin >> c;
if (c > 0){
l[i] = 0;
v[i] = c;
cout << c << '\n';
} else {
c=-c;
l[i] = c;
int idx = getp(i-1,c);
idx = getp(idx-1,c);
for (int j = 0; idx > 0, j < 20; j++){
p[i][j] = idx;
idx = p[idx][j];
}
cout << v[getp(i,1)] << '\n';
}
}
return 0;
}
