Process queue operations using only stack-style push and pop behavior internally.
Return one output per operation. Constructor and push produce null; pop and peek return values; empty returns a boolean.
Inputoperations = ["MyQueue", "push", "push", "peek", "pop", "empty"], values = [[], [1], [2], [], [], []]
Output[null, null, null, 1, 1, false]
Inputoperations = ["MyQueue", "push", "pop", "empty"], values = [[], [7], [], []]
Output[null, null, 7, true]
At most 100 operations are performed.