Problem Statement

We have an integer sequence ~A~ and a notebook. The notebook has ~10^9~ pages.

You are given ~Q~ queries. Each query is of one of the following four kinds:

ADD ~x~ : append an integer ~x~ to the tail of ~A~

DELETE: remove the last term of ~A~ if ~A~

SAVE ~y~ : erase the sequence recorded on the ~y~ -th page of the notebook, and record the current ~A~ onto the ~y~

LOAD ~z~ : replace ~A~ with the sequence recorded on the ~z~

Initially, ~A~ is an empty sequence, and an empty sequence is recorded on each page of the notebook. Process ~Q~ queries successively in the given order and print the last term of ~A~ after processing each query.

The use of fast input and output methods is recommended because of potentially large input and output.

Constraints

• ~1 \leq Q \leq 5 \times 10^5~
• ~1 \leq x, y, z \leq 10^9~
• ~Q~ , ~x~ , ~y~ , and ~z~ are integers.
• Each of the given queries is of one of the four kinds in the Problem Statement.

Input

The input is given from Standard Input in the following format:

~Q~

~\mathrm{query}_1~

~\mathrm{query}_2~

~\vdots~

~\mathrm{query}_Q~

Output

For each ~i = 1, 2, \ldots, Q~ , let ~X_i~ be the last element of ~A~ after processing up to the ~i~ -th query, or let ~X_i := -1~ if ~A~ is empty, and print them in the following format:

~X_1~ ~X_2~ ~\ldots~ ~X_Q~

Sample Input 1

11
ADD 3
SAVE 1
ADD 4
SAVE 2
LOAD 1
DELETE
DELETE
LOAD 2
SAVE 1
LOAD 3
LOAD 1

Sample Output 1

3 3 4 4 3 -1 -1 4 4 -1 4

Initially, ~A~ is an empty sequence, so ~A = ()~ , and an empty sequence is recorded on each page of the notebook.

• By the ~1~ -st query, ~3~ is appended to the tail of ~A~ , resulting in ~A = (3)~ .
• By the ~2~ -nd query, the sequence recorded on the ~1~ -st page of the notebook becomes ~(3)~ . It remains that ~A = (3)~ .
• By the ~3~ -rd query, ~4~ is appended to the tail of ~A~ , resulting in ~A = (3, 4)~ .
• By the ~4~ -th query, the sequence recorded on the ~2~ -nd page of the notebook becomes ~(3, 4)~ . It remains that ~A = (3, 4)~ .
• By the ~5~ -th query, ~A~ is replaced by ~(3)~ , which is recorded on the ~1~ -st page of the notebook, resulting in ~A = (3)~ .
• By the ~6~ -th query, the last term of ~A~ is removed, resulting in ~A = ()~ .
• By the ~7~ -th query, nothing happens because ~A~ is already empty. It remains that ~A = ()~ .
• By the ~8~ -th query, ~A~ is replaced by ~(3,4)~ , which is recorded on the ~2~ -nd page of the notebook, resulting in ~A = (3, 4)~ .
• By the ~9~ -th query, the sequence recorded on the ~1~ -st page of the notebook becomes ~(3, 4)~ . It remains that ~A = (3, 4)~ .
• By the ~10~ -th query, ~A~ is replaced by ~()~ , which is recorded on the ~3~ -rd page of the notebook, resulting in ~A = ()~ .
• By the ~11~ -th query, ~A~ is replaced by ~(3, 4)~ , which is recorded on the ~1~ -st page of the notebook, resulting in ~A = (3, 4)~ .

Sample Input 2

21
ADD 4
ADD 3
DELETE
ADD 10
LOAD 7
SAVE 5
SAVE 5
ADD 4
ADD 4
ADD 5
SAVE 5
ADD 2
DELETE
ADD 1
SAVE 5
ADD 7
ADD 8
DELETE
ADD 4
DELETE
LOAD 5

Sample Output 2

4 3 4 10 -1 -1 -1 4 4 5 5 2 5 1 1 7 8 7 4 7 1