栈和队列_用两个栈实现队列|算法专题

const stack1 = [];
const stack2 = [];

function push(node)
{
    stack1.push(node);
}
function pop()
{
    if(stack2.length === 0){
       while(stack1.length>0){
        stack2.push(stack1.pop());
       }
    }
    return stack2.pop() || null;
}

    const queue1 = []
    const queue2 = []

    function push(x) {
      if (queue1.length === 0) {
        queue1.push(x)

        while (queue2.length) {
          queue1.push(queue2.shift())
        }
      } else if (queue2.length === 0) {
        queue2.push(x)

        while (queue1.length) {
          queue2.push(queue1.shift())
        }
      }
    };

    function pop() {
      if (queue1.length !== 0) {
        return queue1.shift()
      } else {
        return queue2.shift()
      }
    };