Competitions

# Stack Data Structure

# Maximum Frequency Stack

Design a stack-like data structure to push elements to the stack and pop the most frequent element from the stack. The possible commands are:

**push n**- pushes an integer**n**onto the top of the stack;**pop**- removes and prints the most frequent element in the stack. If there is a tie for the most frequent element, the element closest to the stack's top is removed and printed.

#### Input

Each line contains a single command.

#### Output

For each **pop** command print on a separate line the corresponding result.

Input example #1

push 4 push 5 push 4 push 6 push 7 pop push 5 pop pop

Output example #1

4 5 7

Input example #2

push 5 push 3 push 1 push 3 push 9 pop pop pop pop pop

Output example #2

3 9 1 3 5