截取地址栏的query参数

let str = 'http://www.baidu.com?a=1&b=2&c=&d=xxx'

function convertToObj (url) {
    let newstr = url.slice(url.indexOf('?')+1)
    let arr = newstr.split('&')
    let obj = {}
    
       for(let item of arr){
         let i = item.split('=')
         obj[i[0]] = i[1];
       }
    
       return obj
   }
  console.log(convertToObj(str))

第二题：
var arr = [{a:1},{b:2},{c:3},{d:4},{e:5},{f:6},{g:7}]

function finish(list,num) {
    let result = []
    for (let i = 0; i < list.length; i += num) {
        result.push(list.slice(i, i + num))
   }
    return result

}