232. Implement Queue using Stacks

/*
// 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.
*/

class MyQueue {

    Stack<Integer> temp = new Stack<Integer>();
    Stack<Integer> value = new Stack<Integer>();
    
    /** Initialize your data structure here. */
    public MyQueue() {
        
    }
    
    /** Push element x to the back of queue. */
    public void push(int x) {
        if(value.isEmpty()){
            value.push(x);
        }
        else {
            while(!value.isEmpty()) {
                temp.push(value.pop());
            }
 
            value.push(x);
 
            while(!temp.isEmpty()) {
                value.push(temp.pop());
            }    
        }
    }
    
    /** Removes the element from in front of queue and returns that element. */
    public int pop() {
         return value.pop();
    }
    
    /** Get the front element. */
    public int peek() {
        return value.peek();
    }
    
    /** Returns whether the queue is empty. */
    public boolean empty() {
        return value.isEmpty();
    }
}

/**
 * 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();
 * boolean param_4 = obj.empty();
 */