20220513

分糖果问题

输入：[1,1,2]

返回值：4

说明：arr为得分列表，需要根据得分情况，得分高的糖果分得多

function candy( arr ) {
    // write code here
    let len = arr.length;
    if(len<=1) return len;
    let candyNum = 1
    // 记录糖果数量
    let candyArr = new Array(len).fill(candyNum)
    // 遍历查询所有孩子的得分
    // 从左到右看，保证糖果根据分值递增
    //  小--->大
    for(let i=1; i<len; i++) {
        if(arr[i] <= arr[i-1]) continue
        //  小--->大
        candyArr[i]= candyArr[i-1]+1
    }
    // 从右向左看，保证糖果根据分值递递增
    //  大<---小
    for(let i=len-2;i>=0;i--) {
        if(arr[i] <= arr[i+1])continue
        // 过滤糖果非递增项  
        if(candyArr[i] > candyArr[i+1]) continue
        //  大<---小
        candyArr[i] =  candyArr[i+1]+1
    }
    return candyArr.reduce((pre,cur)=>pre+cur,0) 
}

函数链式调用

// 实现效果
LazyMan(“Hank”).eat(“supper”).sleepFirst(5)输出
//等待5秒
Wake up after 5
Hi This is Hank!
Eat supper

let fn1 = (str) => console.log(`Hi! This is ${str}!`);
let fn2 = (delay) => new Promise((resolve) =>
    setTimeout(() => {
        console.log(`Wake up after ${delay}`);
        resolve();
    }, delay)
);

let fn3 = (str) => console.log(`Eat ${str}~!`);

function Task() {
  this.stack = [];
  this.LazyMan = function(param) {
    this.stack.push(fn1.bind(null, param));
    return this;
  };
  this.sleep = function(param) {
    this.stack.push(fn2.bind(null, param));
    return this;
  };
  this.eat = function(param) {
    this.stack.push(fn3.bind(null, param));
    return this;
  };
  this.sleepFirst = function(param) {
    this.stack.unshift(fn2.bind(null, param));
    return this;
  };
  this.start = function() {
    this.stack.reduce((pre, cur) =>
          pre instanceof Promise ? pre.then((res) => cur(res)) : cur(pre), null)
      .then();
    this.stack.length =0
  };
}

let f1 = new Task();
f1.LazyMan("Hank").sleep(5).eat("supper").sleepFirst(5);
f1.start().then();