7. queue with two stacks

7. queue with two stacks

Title Description

Two stacks to achieve a queue, the completion queue Push and Pop operations. Queue elements int.

Problem-solving ideas

• Stack: the stack is inserted into a
• The stack: Stack 2 determines whether the air
  • Empty: Stack 1 elements of all pushed onto the stack 2
  • Stack 2 Stack

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//.js
var stack1 = [];
var stack2 = [];
function push(node)
{
    // write code here
    stack1.push(node);
}
function pop()
{
    // write code here
    if(stack2.length == 0){
        while(stack1.length > 0){
            stack2.push(stack1.pop());
        }
    }
    if(stack2.length >= 0){
       return stack2.pop();
    }
}

//.java
import java.util.Stack;

public class Solution {
    Stack<Integer> stack1 = new Stack<Integer>();
    Stack<Integer> stack2 = new Stack<Integer>();

    public void push(int node) {
        stack1.push(node);
    }

    public int pop() {
        if (stack2.size() == 0) {
            while (stack1.size() > 0) {
                stack2.push(stack1.pop());
            }
        }
        return stack2.pop();
    }
}