Interview 9-use two stacks to implement a queue, complete push and pop operations for the queue

• Topic
  • Implement a queue with two stacks to complete the push and pop operations of the queue. The elements in the queue are of type int.
• Ideas:
  • One stack is pressed into the element, and the other stack acts as a buffer, and the stack 1 element is pushed back into the stack 2.
• Code

Import java.util.stack;/** * Two stacks implementation of a queue * @author MSI */public class requeue{     stack<integer> sk1=new stack< Integer> ();     Stack<integer> sk2=new stack<integer> ();     public void push (int val) {         Sk1.push (val);     }     public int pop () throws exception{//stacks 1 sequentially and presses into the stack 2         if (Sk1.isempty () &&sk2==null) {             throw new Exception ( "Queue is empty");         while (Sk2.isempty ()) {             while (!sk1.isempty ()) {                 Sk2.push (Sk1.pop ());             }         }         return Sk2.pop ();     }    public static void Main (String args[]) throws exception{        requeue q1=new requeue ();        Q1.push (1);        Q1.push (2);        Q1.push (3);        while (q1!=null)        System.out.println (Q1.pop ());               }    }

• Output

• 123

  　　

Interview 9-use two stacks to implement a queue, complete push and pop operations for the queue