SOURCE

function deepCopy(target, hash = new WeakMap()) {
    const type = Object.prototype.toString.call(target).slice(8, -1)
    let res
    if (type === 'Object') res = {}
    else if (type === 'Array') res = []
    else return target
    if (hash.has(target)) return hash.get(target)
    hash.set(target, res)
    for (let key in target) {
        res[key] = deepCopy(target[key], hash)
    }
    return res
}

// const obj = {
//     foo: {
//         azz: [1, 3, 2]
//     },
//     age: [1, {
//         baz: 71
//     }],
//     num: 3
// }
// let objc = deepCopy(obj);
// console.log(obj)
// console.log(objc)
// console.log(objc === obj)

function myall(iterator) {
    return new Promise((resolve, reject) => {
        let reslist = []
        let i = 0
        let len = 0
        for (const p of iterator) {
            let resIndex = len++
            Promise.resolve(p).then((res) => {
                console.log(`${resIndex}: ${res}`);
                reslist[resIndex] = res
                if (++i === len) resolve(reslist)
            }).catch(reject)
        }
        if (len === 0) resolve(reslist)
    })
}
// let arr = [];
// let index = 0;
// while (index < 5) {
//     index += 1;
//     arr.push(
//         new Promise((resolve, reject) => {
//             let num = Math.floor(Math.random() * 5 + 1);
//             setTimeout(() => {
//                 resolve(`${num}s`);
//                 // num > 5 ? resolve(num) : reject(num);
//             }, num * 1000);
//         })
//     );
// }

// myall(arr).then((res) => console.log("res", res)).catch((err) => console.log("err", err));

function asyncPool(poolLimit, urls, request) {
    let ret = [], executing = [], i = 0
    function enqueue() {
        if (i >= urls.length) return Promise.resolve()
        const p = Promise.resolve(request(urls[i++]))
        ret.push(p)
        executing.push(p)
        p.then(() => executing.splice(executing.indexOf(p), 1))
        let r = Promise.resolve()
        if (executing.length >= poolLimit) r = Promise.race(executing)
        return r.then(() => enqueue())
    }
    return enqueue().then(() => Promise.all(ret))
}
// let arr = [];
// let index = 0;
// while (index < 10) {
//   index++;
//   arr.push(index);
// }

// asyncPool(3, arr, (param) => {
//   return new Promise((resolve, reject) => {
//     setTimeout(() => {
//       resolve(param);
//     }, Math.floor(Math.random() * 5 + 1) * 1000);
//   });
// })
// .then((res) => console.log("res", res));

function sort(nums) {
    if (nums.length <= 1) return nums
    let left = [], right = []
    let middleIdx = Math.floor(nums.length / 2)
    let middle = nums.splice(middleIdx, 1)[0]
    nums.forEach(item => {
        if (item < middle) left.push(item)
        else right.push(item)
    })
    return sort(left).concat(middle, sort(right))
}


// console.log(sort([5, 1, 3, 4, 2]))

var removeDuplicates = function (nums) {
    let res = []
    nums.forEach(item => {
        if (res.indexOf(item) === -1) res.push(item)
    })
    return res
};

// console.log(removeDuplicates([5, 5, 6, 7, 6, 1, 1, 3, 4, 2]))

function search(nums, target) {
    let left = 0, right = nums.length - 1
    while (left <= right) {
        let middle = Math.floor(left + (right - left) / 2)
        if (nums[middle] === target) return middle
        let isSmall = nums[middle] < target
        left = isSmall ? middle + 1 : left
        right = isSmall ? right : middle - 1
    }
    return -1
}
// console.log(search([-1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 6))

function Parent() {
    this.hobby = ['跑步']
}
Parent.prototype.showHobby = function () {
    console.log(this.hobby)
}

function Child(name) {
    this.name = name
    Parent.call(this)
}

Child.prototype = new Parent()
Child.prototype.constructor = Child
Child.prototype.showName = function () {
    console.log(this.name)
}


function myNew(fn, ...args) {
    const obj = Object.create(fn.prototype)
    const ret = fn.apply(obj, args)
    return ret instanceof Object ? ret : obj
}

// let c = new Child('zhang san')
// let d = myNew(Child, 'zhang san')
// console.log(c.__proto__)
// console.log(d.__proto__)
// c.showHobby()
// d.showHobby()
// c.showName()
// d.showName()