#include<iostream>
using namespace std;
const int N = 100010;
int e[N], ne[N];
int head, idx;

void init(){
    head = -1;
    idx = 0;
}

void insert_to_head(int x) {
    e[idx] = x;
    ne[idx] = head;
    head = idx;
    idx ++ ;
}

void insert(int k, int x) {
    e[idx] = x;
    ne[idx] = ne[k];
    ne[k] = idx;
    idx ++ ;
}

void delet(int k) {
    ne[k] = ne[ne[k]];
}

int main(){
    int m;
    scanf("%d", &m);
    init();
    while(m -- ) {
        char opt;
        cin >> opt;
        if (opt == 'H') {
            int x;
            cin >> x;
            insert_to_head(x);
        }
        if (opt == 'D') {
            int k;
            cin >> k;
            if (k == 0) head = ne[head];
            else delet(k - 1);
        }
        if (opt == 'I') {
            int k, x;
            cin >> k >> x;
            insert(k - 1, x);
        }
    }
    for (int i = head; i != -1; i = ne[i] ) cout << e[i] << " ";

}