Implement the following operations of a queue using stacks.

- push(x) — Push element x to the back of queue.
- pop() — Removes the element from in front of queue.
- peek() — Get the front element.
- empty() — Return whether the queue is empty.

**Example:**

MyQueue queue = new MyQueue(); queue.push(1); queue.push(2); queue.peek(); // returns 1 queue.pop(); // returns 1 queue.empty(); // returns false

**Notes:**

- You must use
*only*standard operations of a stack — which means only`push to top`

,`peek/pop from top`

,`size`

, and`is empty`

operations are valid. - Depending on your language, stack may not be supported natively. You may simulate a stack by using a list or deque (double-ended queue), as long as you use only standard operations of a stack.
- You may assume that all operations are valid (for example, no pop or peek operations will be called on an empty queue).

## C# Program

public class MyQueue { Stack<int> inputStack; Stack<int> outputStack; /** Initialize your data structure here. */ public MyQueue() { inputStack = new Stack<int>(); outputStack = new Stack<int>(); } /** Push element x to the back of queue. */ public void Push(int x) { inputStack.Push(x); } /** Removes the element from in front of queue and returns that element. */ public int Pop() { if(outputStack.Count > 0) return outputStack.Pop(); else { while(inputStack.Count > 0) outputStack.Push(inputStack.Pop()); } return outputStack.Pop(); } /** Get the front element. */ public int Peek() { if(outputStack.Count > 0) return outputStack.Peek(); else { while(inputStack.Count > 0) outputStack.Push(inputStack.Pop()); } return outputStack.Peek(); } /** Returns whether the queue is empty. */ public bool Empty() { return inputStack.Count == 0 && outputStack.Count == 0; } } /** * Your MyQueue object will be instantiated and called as such: * MyQueue obj = new MyQueue(); * obj.Push(x); * int param_2 = obj.Pop(); * int param_3 = obj.Peek(); * bool param_4 = obj.Empty(); */

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