Center Out Dispatch Decoder

A dispatcher stores a message using a center-out deque process. Starting with an empty deque, character i of the original message, using zero-based indexing, is appended to the right end when i is even and to the left end when i is odd. The stored message is the final deque read from left to right. Given the stored message, recover the original message. Input Format: The first line contains t, the number of test cases. Each test case contains n and the stored string. Output Format: For each test case, print the recovered original message.