题解 | #栈的压入、弹出序列#

可以使用数组模拟栈的操作,主要要熟悉判断压入和弹出的判断方法

function IsPopOrder(pushV, popV)
{
    let stack = new Stack();
    let popNum=0;

    for(let i=0;i<pushV.length;i++){
        stack.push(pushV[i]);
        //while 不断对比栈顶元素，检查了 pushA压栈过程中出栈的情况。
        while(!stack.isEmpty()&&stack.peek()==popV[popNum]){
            stack.pop();
            popNum++;
        }
    }
    return stack.isEmpty();
}
class Stack {
    constructor() {
        this.item = [];
    }

    push = function (element) {
        this.item.push(element)
    }

    pop = function () {
        return this.item.pop();
    }
    peek = function () {
        return this.item[this.item.length - 1];
    }
    isEmpty = function () {
        return this.item.length === 0;
    }
    toString = function () {
        let res = '';
        this.item.forEach( item => {
            res += item + ''
        })
        return res;
    }
}

module.exports = {
    IsPopOrder : IsPopOrder
};