操作数组

//获取数组最大值
var arr = [12, 5, 41, 14, 65, 11, 32];
var count = Math.max.apply(this, arr);
console.log(count);//65

//排序

var arr = [12, 5, 41, 14, 65, 11, 32];

arr.sort(function(a,b){

　　//return a-b;//升序

　　return b-a;//降序

});

//数组颠倒过来

var arr = [12, 5, 41, 14, 65, 11, 32];

arr.reverse();//arr:32,11,65,14,41,5,12