数组去重

链接：https://www.nowcoder.com/questionTerminal/0b5ae9c4a8c546f79e2547c0179bfdc2 来源：牛客网    var resArr = [];    var flag = true;          for(var i=0;i<this.length;i++){        if(resArr.indexOf(this[i]) == -1){            if(this[i] != this[i]){   //排除 NaN               if(flag){                    resArr.push(this[i]);                    flag = false;               }            }else{                 resArr.push(this[i]);            }        }    }     return resArr;