-_-#求数组最大数

var arr = [3, 342, 23, 22, 123]
var max = Math.max.apply(null, arr)
console.log(max)

var arr = [3, 342, 23, 22, 123]
arr.sort(function(a, b) {
    return b - a
})
var max = arr[0]
console.log(max)