Problem Description
Remember the priority_queue data structure that pops out the greatest element every time? Now, you have to implement a data structure that is similar to priority_queue, but does not pop out the greatest element, but pops out the element according to the following rules:
- If the size of the queue is odd, pop out the middle element. (i.e. the median)
- Otherwise, pop out the element to the left of the middle.
Given a list of PUSH and POP instructions, output the resultant queue in ascending order.
Input
The first line of input will contain N, the number of instructions.
The following N lines of input will contain either a PUSH x, where you will be required to push an integer x into the queue, or a POP instruction, where you will be required to pop an integer out of the queue according to the instructions above.
Output
Your output should contain a list of space-seperated integers, which represents the resultant queue in ascending order.
Your output should be terminated with a newline.
Limits
Subtask 1 (36%): 1 ≤ N ≤ 1 000
Subtask 2 (64%): 1 ≤ N ≤ 1 000 000
Subtask 3 (0%): As per sample testcases
Sample Input 1
5
PUSH 5
PUSH 2
POP
PUSH 3
PUSH 9
Sample Output 1
3 5 9