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一、数组处理

1. 数组去重

1. 纯数组去重(6种方法)

class ArrayToHeavy {
      // new Set去重
      newSetHeavy(arr) {
        return Array.from(new Set(arr))
      }

      // .indexOf或lastIndexOf去重
      indexHeavy(arr) {
        let newArr = [];
        arr.forEach((val, index) => {
          newArr.indexOf(val) === -1 ? newArr.push(val) : '';
        });
        return newArr
      }

      // 通过filter过滤返回一个新数组在原数组中对比用indexof去重
      filterHeavy(arr) {
        return arr.filter((item, index, self) => {
          return self.indexOf(item) === index; //比较数组中每一项是否为其（indexof）首次查找的索引值(index)
        })
      }

      // 通过splice改变原数组去重
      spliceHeavy(arr) {
        let len = arr.length;
        for (let i = 0; i < len; i++) {
          for (let j = i + 1; j < len; j++) {
            if (arr[i] == arr[j]) {
              arr.splice(j, 1);
              len--;
              j--
            }
          }
        }
      }

      /* 相邻元素去重
       这种方法首先调用了数组的排序方法sort()，然后根据排序后的结果进行遍历及相邻元素比对，
       如果相等则跳过改元素，直到遍历结束 */
      uniqueHeavy(arr) {
        if (!Array.isArray(arr)) {
          console.log('type error!')
          return
        }
        arr = arr.sort()
        let res = []
        for (let i = 0; i < arr.length; i++) {
          if (arr[i] !== arr[i - 1]) {
            res.push(arr[i])
          }
        }
        return res
      }

      /* 利用对象属性去重
        创建空对象，遍历数组，将数组中的值设为对象的属性，并给该属性赋初始值1，
        每出现一次，对应的属性值增加1，这样，属性值对应的就是该元素出现的次数了 */
     ObjHeavy(arr) {
      if (!Array.isArray(arr)) {
        console.log('type error!')
        return
      }
      let res = [],
        obj = {}
      for (let i = 0; i < arr.length; i++) {
        if (!obj[arr[i]]) {
          res.push(arr[i])
          obj[arr[i]] = 1
        } else {
          obj[arr[i]]++
        }
      }
      return res
    }
    }
    const ArrayToHeavy_handle = new ArrayToHeavy()
    console.log(ArrayToHeavy_handle.newSetHeavy([1, 1])) // [1]

2. 对象数组去重

1. 去重相同id的对象

let person = [
{ id: 0, name: "A" },
{ id: 0, name: "b" }
];

let obj = {};
let peon = person.reduce((cur, next) => {
  obj[next.id] ? "" : (obj[next.id] = true && cur.push(next));
  return cur;
}, []); //设置cur默认类型为数组，并且初始值为空的数组
peon // [{ id: 0, name: "A" }]

2. 数组排序10种实用方法

{1} 冒泡排序

• 解释：冒泡排序算法就是依次比较大小，小的的大的进行位置上的交换。
• 实现原理：
  当i=0的时候，里面的循环完整执行，从j=0执行到j=6,这也就是第一遍排序，结果是将最大的数排到了最后，这一遍循环结束后的结果应该是[8,34,21,53,12,95

当i=1的时候，里面的循环再次完整执行，由于最大的数已经在最后了，没有必要去比较数组的最后两项，这也是j说到这里，规律就清楚了，每次将剩下数组里面最大的一个数排到最后面，当第一个循环执行到最后的时候，也就是i=6,此时，j=0,只需要比较数组的第一和第二项，比较完毕，返回。

let arr=[8,95,34,21,53,12];
 function sortarr(arr){
  for(i=0;iarr[j+1]){
     var temp=arr[j];
     arr[j]=arr[j+1];
     arr[j+1]=temp;
    }
   }
  }
  return arr;
 }
 sortarr(arr); // [8,12,21,34,53,95]

(2) 选择排序

• 解释：依次找到剩余元素最小值，放置排好序的末尾（第一个放在开头）
  在时间复杂度上表现最稳定的排序算法之一，因为无论什么数据进去都是O(n²)的时间复杂度，所以用到它的时候，数据规模越小越好。唯一的好处可能就是不占用额外的内存空间

  function selectionSort(arr) {
  var len = arr.length;
  var minIndex, temp;
  for (var i = 0; i < len - 1; i++) {
      minIndex = i;
      for (var j = i + 1; j < len; j++) {
          if (arr[j] < arr[minIndex]) {     //寻找最小的数
              minIndex = j;                 //将最小数的索引保存
          }
      }
      temp = arr[i];
      arr[i] = arr[minIndex];
      arr[minIndex] = temp;
  }
  return arr;
  }

  3. 数组拷贝

  (1) [].concat.apply([], 被拷贝的数组) 适合处理一维数组

let a = [1,2];
let b = [].concat.apply([], a);
b[0] = 0;
a // => [1, 2]
b // => [0, 2]

4.处理二维数组

(1) 将连续的二维数组中的对应索引项合并为一个数组，返回合并后的二维数组

输入：
var data = [
[2001, 10, 20],
[2002, 30 ,40],
[2003, 50 ,60]
]
输出：
[
[2001, 2002, 2003],
[10, 30, 50],
[20, 40, 60]
]

实现：
    var getBarData = [];
    data[0].map(item => {
      getBarData.push([])
    });
    data.forEach((item, inx) => {
      for(var i = 0; i < data[0].length; i++) {
        getBarData[i].push(item[i])
      }
    })

5. 按指定条件查找数组中的元素

(1) 查找数组最大值

 输入:   let a = [1,2,3,4]
 输出： 4

1. 利用Math方法通过apply 将数组元素一个一个拆分开来，然后在传递到Math.max()方法中
Math.max.apply(null, a)

2. Math.max(...a)

3. 利用sort方法
    let resultArr = a.sort(function(a, b) {
      return b - a;
     });
     resultArr[0] // 5

6. 按指定条件过滤数组

(1) 过滤数组中值为 false 的值

输入： let a = [0,0,false,null,3]
输出： [3]

let b = a.filter(Boolean) // [3]

7. 类数组转为数组

(1) [].slice.call(obj) 或Array.prototype.slice.call(obj) 或 Array.prototype.concat.apply([],obj)

[].slice.call({length:2,0:1,1:2}) // [1 ,2]
Array.prototype.concat.apply([],{length:1,0:1}) // [1]

(2) Array.from(cArr) 或 [...obj]

Array.from({length:1,0:1}) // [1]

8.扁平化数组

输入: var arr = [[[1,2,3],[[4,5,6]]]]
输出: [1,2,3,4,5,6]

(1) reduce递归法

 var flatten = (arr) => {
          return arr.reduce((pre, next) => {
              return pre.concat(Array.isArray(next) ? flatten(next) : next);
          }, [])
         }
        flatten(arr) // [1,2,3,4,5,6]

二、对象处理

1. 将对象转为数组

• 利用Object.keys()

  const obj = {
       "sex_wxx": "性别",
       "income_wxx": "收入",
       "age_wxx": "年龄"
   };
   let arr = [];
   Object.keys(obj).forEach(v => {
       let o = {};
       o[v] = obj[v];
       arr.push(o)
   })
  console.log(arr) // [{sex_wxx: '性别'}, {income_wxx: '收入'},{age_wxx: '年龄'}]

• 利用Object.entries()

Object.entries(obj).forEach(item => {
 let o = {}
o[item[0]] = item[1]
arr.push(o)
})

• Object.keys()和map()结合

Object.keys(obj).map(v => { return v = {[v]: obj[v]} })

2. 递归对象获取value

var obj = { a:{w:1,y:2,x:3},
b:{s:4,j:5,x:6},
c:{car:7,cat:8,mao:9}
}
function f(s){
for(var i in s){
if(typeof s[i]=="object"){
f(s[i])
}else{
　　　console.log(s[i]);
　　}
}
}
f(obj) // 1,2,3,4,5,6,7,8,9

3. 判断两个对象是否相等

Object.entries({name:1}).toString() === Object.entries({name:1}).toString() // true

4. 从一个对象条件匹配另一个对象

用过滤（filter）判断（every）每一项是否符合条件

let obj = {name:  'ops'}
let arr = [{name: 'q'}, {name: 'ops', kl: 'oop'}]
var _key= Object.keys(obj)

arr.filter(item=>_key.every(k=>obj[k]===item[k])) // {name: 'ops', kl: 'oop'}

5. 对象转为url参数拼接

输入：

{
a:1,
b:2
}

输出：

a=1&b=2

function obj2strUrl (obj) {
    let str="";
    for (let key in obj) {
      str = `${str}${key}=${obj[key]}&`
    };
    str = str.substring(0, str.length-1);
    return str;
}

反转：拼接的url参数转为对象

/**
 * @param {string} url
 * @returns {Object}
 */
function param2Obj(url) {
  const search = decodeURIComponent(url.split('?')[1]).replace(/\+/g, ' ')
  if (!search) {
    return {}
  }
  const obj = {}
  const searchArr = search.split('&')
  searchArr.forEach(v => {
    const index = v.indexOf('=')
    if (index !== -1) {
      const name = v.substring(0, index)
      const val = v.substring(index + 1, v.length)
      obj[name] = val
    }
  })
  return obj
}

三、字符串处理

1. 将被字符串包裹的对象转为js对象

输入 '{name: qwer, id: 1, ops: poi}',=> 输出 {name: 'qwer', id: '1', ops: 'poi'}

function strToObj(str) {
    let arr = str.replace(/{|}|\s*/g, '').split(','),
        obj = {}
    arr.forEach(val => {
        let i = val.indexOf(':')
        obj[val.substr(0, i)] = val.substr(i + 1);
});
return obj
}
console.log(strToObj('{name: qwer, id: 1, ops: poi}')) => {name: 'qwer', id: '1', ops: 'poi'}

2. 格式化string/number类型的日期

let date = '20220408000009';
function f(str, type) {
let i = 0,_type = type || 'xxxx-xx-xx xx:xx:xx'
return _type.replace(/x/g, () => str[i++])
}
f(date)

3. 计算字符串宽度（px）

// 1. 精确计算
function computedTextWidth (text) {
    var canvas = document.createElement('canvas');
     canvas.id = 'computedTextWidth';
     canvas.style.cssText = 'visibility:hidden;position: absolute;left: -999em;top:-999em;';
     document.body.appendChild(canvas);
    var context = canvas.getContext('2d');
    context.font = '12px';
    context.fillText(text, 0, 0);
    return context.measureText(text).width;
}
computedTextWidth('33333333') // 100

// 2. 误差计算(差值为1/4)
computedTextWidth(text, fontSize = 14) {
  let span = document.getElementById('computedTextWidth');
  if (!span) {
    span = document.createElement('span');
    span.id = 'computedTextWidth';
    span.style.cssText = 'visibility:hidden;position: absolute;left: -999em;top:-999em;';
    document.body.appendChild(span);
  }
  span.style.fontSize = `${fontSize}px`;
  span.innerHTML = text;
  return span.offsetWidth;
};

4. 提取字符串中的数字

(1) match方法

var str = '123AAAA098'
var numArr = str.match(/\d+/g)
    numArr // => ["123", "098"]

(2) replace方法

var s ="4500元，6,700";
var num= s.replace(/[^0-9]/ig,"");
num // 45006700

5. 提取字符串中的指定值(度量值)

let str = '申请量 3 件，总量 3,541，98234，4.5，90% ，4.5%件。';
str.match(/\d+(.\d+\%)|\d+(,\d+)|\d+(\.\d+)|\d+\%|\d+/img);
str // ['3', '3,541', '98234', '4.5', '90%', '4.5%']

四、日期时间类

1. 根据开始时间 + 日/月/年数 计算截止日期

(1) 开始日期+天数=截止日期

export function getEndDay(dateTemp, days) {
  dateTemp = dateTemp.split("-")
  var nDate = new Date(dateTemp[1] + "-" + dateTemp[2] + "-" + dateTemp[0]) // 格式化时间
  var millSeconds = Math.abs(nDate) + days * 24 * 60 * 60 * 1000
  var rDate = new Date(millSeconds)
  var year = rDate.getFullYear()
  var month = rDate.getMonth() + 1
  if (month < 10) month = "0" + month
  var date = rDate.getDate()
  if (date < 10) date = "0" + date
  return year + "-" + month + "-" + date
}
使用： getEndDay('年-月-日', '天数')
例： getEndDay('2021-11-11', '1')  =>  '2021-11-12'

(2) 开始日期+月数=截止日期

 export function getEndMonth(dtstr, n) {
     var s = dtstr.split("-")
     var yy = parseInt(s[0])
     var mm = parseInt(s[1])
     var dd = parseInt(s[2])
     var dt = new Date(yy, mm, dd)
     
     var num=dt.getMonth() + parseInt(n)
     if(num/12>1){
        yy+=Math.floor(num/12)
        mm=num%12
     }else{
         mm+=parseInt(n)
     }
     return yy + "-" + mm  + "-" + dd
 }
 使用： getEndMonth('年-月-日', '月数')
 例： getEndMonth('2021-11-11', '1')  =>  '2021-12-11'

(3)开始日期+年数=截止日期

export function getEndYear(date, years) {
  var now = new Date(date);
  var intYear = now.getFullYear() + parseInt(years);
  var intMonth = now.getMonth() + 1; //正常的月份，
  var intDay = now.getDate() - 1; //日期-1
  if (intDay == 0) {
  intMonth--; //减少一个月
  if (intMonth == 0) {
  intYear--; //0:减少一年
  intMonth = 12;
  intDay = 31;
  }
  else if (intMonth == 4 || intMonth == 6 || intMonth == 9 || intMonth == 11) {
  intDay = 30; //4,6,9,11:30天
  }
  else if (intMonth == 2) {
  intDay = 28; //2:28/29
  if (intYear % 4 == 0) {
  intDay = 29;
  }
  } else {
  intDay = 31; //1,3,5,7,8,10,12 :31天
  }
  }

  var strMonth = (intMonth) < 10 ? "0" + (intMonth).toString() : (intMonth).toString();
  var strDay = (intDay) < 10 ? "0" + (intDay).toString() : (intDay).toString();
  var strEndDate = intYear + "-" + strMonth + "-" + strDay;
  return strEndDate;
  }
  使用： getEndYear('年-月-日', '月数') 
  例： getEndYear('2021-11-11', '1') => '2022-12-11'

2. 获取指定日期时间

export function timeStremHandle() {
  let now = new Date() //当前日期
  let nowDayOfWeek = now.getDay() //今天本周的第几天
  let nowDay = now.getDate() //当前日
  let nowMonth = now.getMonth() //当前月
  let nowYear = now.getYear() //当前年
  nowYear += (nowYear < 2000) ? 1900 : 0

  let lastMonthDate = new Date() //上月日期
  lastMonthDate.setDate(1)
  lastMonthDate.setMonth(lastMonthDate.getMonth() - 1)
  let lastYear = lastMonthDate.getYear()
  let lastMonth = lastMonthDate.getMonth()

  return {
// 格式化日期：yyyy-MM-dd
    formatDate(date) {
      var myyear = date.getFullYear()
      var mymonth = date.getMonth() + 1
      var myweekday = date.getDate()

      if (mymonth < 10) {
        mymonth = "0" + mymonth
      }
      if (myweekday < 10) {
        myweekday = "0" + myweekday
      }
      return (myyear + "-" + mymonth + "-" + myweekday)
    },
    
    // 获取连续数字年月日
    getNumDate(){
      function formatNumber(n) {
        n = n.toString()
       return n[1] ? n : '0' + n
        }
      function formatDay (date) {
       var year = date.getFullYear()
       var month = date.getMonth() + 1
       var day = date.getDate()
       return [year, month, day].map(formatNumber).join('') + '' 
    }
        
     调用： formatDay(new Date()) // '20220923'
    },

//获得某月的天数
    getMonthDays(myMonth) {
      var monthStartDate = new Date(nowYear, myMonth, 1)
      var monthEndDate = new Date(nowYear, myMonth + 1, 1)
      var days = (monthEndDate - monthStartDate) / (1000 * 60 * 60 * 24)
      return days
    },

//获得本季度的开端月份
    getQuarterStartMonth() {
      var quarterStartMonth = 0
      if (nowMonth < 3) {
        quarterStartMonth = 0
      }
      if (2 < nowMonth && nowMonth < 6) {
        quarterStartMonth = 3
      }
      if (5 < nowMonth && nowMonth < 9) {
        quarterStartMonth = 6
      }
      if (nowMonth > 8) {
        quarterStartMonth = 9
      }
      return quarterStartMonth
    },

//获得本周的开端日期
    getWeekStartDate() {
      var weekStartDate = new Date(nowYear, nowMonth, nowDay - nowDayOfWeek)
      return formatDate(weekStartDate)
    },

//获得本周的停止日期
    getWeekEndDate() {
      var weekEndDate = new Date(nowYear, nowMonth, nowDay + (6 - nowDayOfWeek))
      return formatDate(weekEndDate)
    },

//获得本月的开端日期
    getMonthStartDate() {
      var monthStartDate = new Date(nowYear, nowMonth, 1)
      return formatDate(monthStartDate)
    },

//获得本月的停止日期
    getMonthEndDate() {
      var monthEndDate = new Date(nowYear, nowMonth, getMonthDays(nowMonth))
      return formatDate(monthEndDate)
    },

//获得上月开端日期
    getLastMonthStartDate() {
      var lastMonthStartDate = new Date(nowYear, lastMonth, 1)
      return formatDate(lastMonthStartDate)
    },

//获得上月停止日期
    getLastMonthEndDate() {
      var lastMonthEndDate = new Date(nowYear, lastMonth, getMonthDays(lastMonth))
      return formatDate(lastMonthEndDate)
    },

//获得本季度的开端日期
    getQuarterStartDate() {

      var quarterStartDate = new Date(nowYear, getQuarterStartMonth(), 1)
      return formatDate(quarterStartDate)
    },

//获得本季度的截止日期
    getQuarterEndDate() {
      var quarterEndMonth = getQuarterStartMonth() + 2
      var quarterStartDate = new Date(nowYear, quarterEndMonth, getMonthDays(quarterEndMonth))
      return formatDate(quarterStartDate)
    },
    
//日期减
    DateDiff(sDate1, sDate2) {
      var aDate, oDate1, oDate2, iDays
      aDate = sDate1.split("-")
      oDate1 = new Date(aDate[0], aDate[1] - 1, aDate[2])
      aDate = sDate2.split("-")
      oDate2 = new Date(aDate[0], aDate[1] - 1, aDate[2])
      iDays = parseInt(Math.abs(oDate1 - oDate2) / 1000 / 60 / 60 / 24)
      if ((oDate1 - oDate2) < 0) {
        return -iDays
      }
      return iDays
    },

// 最近一个月年月日
 latelyTimeStrem() {
  var strem = new Date(now)
  strem.setDate(now.getDate() - 30)
  return {
    startDay: this.formatDate(new Date(nowYear, nowMonth, nowDay -30)),
    nowDay: this.formatDate(new Date(nowYear, nowMonth, nowDay))
  }
 }
  }
}

3. 获取当前时间戳

export function getTime(type) {
    if (type === 'start') {
      return new Date().getTime() - 3600 * 1000 * 24 * 90
    } else {
      return new Date(new Date().toDateString())
    }
  }

4. 将时间戳转为 {y}-{m}-{d} {h}:{i}:{s}

/**
 * @param {(Object|string|number)} time
 * @param {string} cFormat
 * @returns {string | null}
 * @description 时间戳转为年月日时分秒
 * @example parseTime(1656577144101)  2022-06-30 16:19:04; 
 *          获取星期几:parseTime(1656577144101, '{y}-{m}-{d} {h}:{i}:{s}{a}'); 2022-06-30 16:19:04四
 */
export function parseTime(time, cFormat) {
  if (arguments.length === 0 || !time) {
    return null
  }
  const format = cFormat || '{y}-{m}-{d} {h}:{i}:{s}'
  let date
  if (typeof time === 'object') {
    date = time
  } else {
    if ((typeof time === 'string')) {
      if ((/^[0-9]+$/.test(time))) {
        time = parseInt(time)
      } else {
        // https://stackoverflow.com/questions/4310953/invalid-date-in-safari
        time = time.replace(new RegExp(/-/gm), '/')
      }
    }

    if ((typeof time === 'number') && (time.toString().length === 10)) {
      time = time * 1000
    }
    date = new Date(time)
  }
  const formatObj = {
    y: date.getFullYear(),
    m: date.getMonth() + 1,
    d: date.getDate(),
    h: date.getHours(),
    i: date.getMinutes(),
    s: date.getSeconds(),
    a: date.getDay()
  }
  const time_str = format.replace(/{([ymdhisa])+}/g, (result, key) => {
    const value = formatObj[key]
    // Note: getDay() returns 0 on Sunday
    if (key === 'a') { return ['日', '一', '二', '三', '四', '五', '六'][value ] }
    return value.toString().padStart(2, '0')
  })
  return time_str
}

5. 获取系统时分秒

  export function getSystemTime() {
    let timer = null
    setInterval(function () {
      let time = new Date()
      let hour = checkTime(time.getHours())
      let minite = checkTime(time.getMinutes())
      let second = checkTime(time.getSeconds())
      function checkTime(i) {
        if (i < 10) return "0" + i
        return i
      }
      timer = hour + ":" + minite + ":" + second
      return timer
    }, 1000)
  }

6.计算两个日期之间的间隔

const dayDif = (date1, date2) =>
Math.ceil(Math.abs(date1.getTime() - date2.getTime()) / 86400000)
dayDif(new Date("2022-11-3"), new Date("2022-2-1"))  // 275

7. 查找日期位于一年中的第几天

const dayOfYear = (date) => Math.floor((date - new 
Date(date.getFullYear(), 0, 0)) / 1000 / 60 / 60 / 24);
dayOfYear(new Date());   // 311

五、 屏蔽浏览器控制台

1.写一个回调函数，让页面进行死循环

!function(){
        var _0x1cbb = ["tor", "struc", "call", "ger", "con", "bug", "de", "apply"];
        setInterval(check, 2e3);
        function check() {
            function doCheck(_0x1834ff) {
                if (('' + _0x1834ff / _0x1834ff)['length'] !== 0x1 || _0x1834ff % 0x14 === 0x0) {
                    (function() {return !![]}[
                        _0x1cbb[0x4] + _0x1cbb[0x1] + _0x1cbb[0x0]
                    ](
                        _0x1cbb[0x6] + _0x1cbb[0x5] + _0x1cbb[0x3]
                    )[_0x1cbb[0x2]]());
                } else {
                    (function() {return ![]}[
                        _0x1cbb[0x4] + _0x1cbb[0x1] + _0x1cbb[0x0]
                    ](
                        _0x1cbb[0x6] + _0x1cbb[0x5] + _0x1cbb[0x3]
                    )[_0x1cbb[0x7]]());
                }
                doCheck(++_0x1834ff);
            }
            try {
                doCheck(0)
            } catch(err) { }
        };
      }();

六、加密算法

SHA加密

解释： SHA-1是一种数据加密算法，该算法的思想是接收一段明文，然后以一种不可逆的方式将它转换成一段（通常更小）密文，也可以简单的理解为取一串输入码（称为预映射或信息），并把它们转化为长度较短、位数固定的输出序列即散列值（也称为信息摘要或信息认证代码）的过程。

function encodeUTF8 (s) {
        var i, r = [], c, x
        for (i = 0; i < s.length; i++)
        if ((c = s.charCodeAt(i)) < 0x80) r.push(c)
        else if (c < 0x800) r.push(0xC0 + (c >> 6 & 0x1F), 0x80 + (c & 0x3F))
        else {
            if ((x = c ^ 0xD800) >> 10 == 0) //对四字节UTF-16转换为Unicode
            c = (x << 10) + (s.charCodeAt(++i) ^ 0xDC00) + 0x10000,
                r.push(0xF0 + (c >> 18 & 0x7), 0x80 + (c >> 12 & 0x3F))
            else r.push(0xE0 + (c >> 12 & 0xF))
            r.push(0x80 + (c >> 6 & 0x3F), 0x80 + (c & 0x3F))
        }
        return r
    }
function sha (s) { // sh1 编码
          var data = new Uint8Array(encodeUTF8(s))
          var i, j, t
          var l = ((data.length + 8) >>> 6 << 4) + 16, s = new Uint8Array(l << 2)
          s.set(new Uint8Array(data.buffer)), s = new Uint32Array(s.buffer)
          for (t = new DataView(s.buffer), i = 0; i < l; i++)s[i] = t.getUint32(i << 2)
          s[data.length >> 2] |= 0x80 << (24 - (data.length & 3) * 8)
          s[l - 1] = data.length << 3
          var w = [], f = [
            function () { return m[1] & m[2] | ~m[1] & m[3] },
            function () { return m[1] ^ m[2] ^ m[3] },
            function () { return m[1] & m[2] | m[1] & m[3] | m[2] & m[3] },
            function () { return m[1] ^ m[2] ^ m[3] }
          ], rol = function (n, c) { return n << c | n >>> (32 - c) },
            k = [1518500249, 1859775393, -1894007588, -899497514],
            m = [1732584193, -271733879, null, null, -1009589776]
          m[2] = ~m[0], m[3] = ~m[1]
          for (i = 0; i < s.length; i += 16) {
            var o = m.slice(0)
            for (j = 0; j < 80; j++)
              w[j] = j < 16 ? s[i + j] : rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1),
                t = rol(m[0], 5) + f[j / 20 | 0]() + m[4] + w[j] + k[j / 20 | 0] | 0,
                m[1] = rol(m[1], 30), m.pop(), m.unshift(t)
            for (j = 0; j < 5; j++)m[j] = m[j] + o[j] | 0
          }
          t = new DataView(new Uint32Array(m).buffer)
          for (var i = 0; i < 5; i++)m[i] = t.getUint32(i << 2)
        
          var hex = Array.prototype.map.call(new Uint8Array(new Uint32Array(m).buffer), function (e) {
            return (e < 16 ? "0" : "") + e.toString(16)
          }).join("")
          return hex
    }
sha(123456); // 7c4a8d09ca3762af61e59520943dc26494f8941b