# Implement Stack using Queues

Implement the following operations of a stack using queues.

• push(x) — Push element x onto stack.
• pop() — Removes the element on top of the stack.
• top() — Get the top element.
• empty() — Return whether the stack is empty.

Example:

```MyStack stack = new MyStack();

stack.push(1);
stack.push(2);
stack.top();   // returns 2
stack.pop();   // returns 2
stack.empty(); // returns false```

Notes:

• You must use only standard operations of a queue — which means only `push to back``peek/pop from front``size`, and `is empty` operations are valid.
• Depending on your language, queue may not be supported natively. You may simulate a queue by using a list or deque (double-ended queue), as long as you use only standard operations of a queue.
• You may assume that all operations are valid (for example, no pop or top operations will be called on an empty stack).

## Solution

```public class MyStack {

Queue queue;
/** Initialize your data structure here. */
public MyStack() {
queue = new Queue();
}

/** Push element x onto stack. */
public void Push(int x) {
queue.Enqueue(x);
for(int i=0;i<queue.Count-1;i++)
{
queue.Enqueue(queue.Dequeue());
}
}

/** Removes the element on top of the stack and returns that element. */
public int Pop() {
return (int)(queue.Dequeue());
}

/** Get the top element. */
public int Top() {
return (int)(queue.Peek());
}

/** Returns whether the stack is empty. */
public bool Empty() {
return queue.Count == 0;
}
}

/**
* Your MyStack object will be instantiated and called as such:
* MyStack obj = new MyStack();
* obj.Push(x);
* int param_2 = obj.Pop();
* int param_3 = obj.Top();
* bool param_4 = obj.Empty();
*/
```