直接上题
Given a queue with operations such as push()and pop() and another attribute named version number which is incremented each time an operation is performed on the queue find the state of the queue at a particular version number without using a lot of memory.
Example:
Input: [[0,1],[0,2],[1],[1],[0,3]], version=3
Output: [2]
Explanation: Version 1: [1], Version 2: [1,2], Version 3: [2], Version 4: [], Version 5: [3]
Format: Push = [0,element], Pop = [1]
没做出来，已挂