codewars--js--Find The Parity Outlier

问题描述：（找出奇数数组中唯一的偶数，或是偶数数组中唯一的奇数）

You are given an array (which will have a length of at least 3, but could be very large) containing integers. The array is either entirely comprised of odd integers or entirely comprised of even integers except for a single integer N. Write a method that takes the array as an argument and returns this "outlier" N.

Examples

[2, 4, 0, 100, 4, 11, 2602, 36]
Should return: 11 (the only odd number)

[160, 3, 1719, 19, 11, 13, -21]
Should return: 160 (the only even number)

我的答案：

 function findOutlier(integers){
   //your code here
   var odd=[];
   var even=[];
   for( var i=0;i<integers.length;i++){
     if(integers[i]%2==0){
       even.push(integers[i]);
     }else{odd.push(integers[i]);}
   }
   if(even.length==1){return even.pop();}
   else{return odd.pop();}

 }

优秀答案：
（1）

 function findOutlier(int){
   var even = int.filter(a=>a%2==0);
   var odd = int.filter(a=>a%2!==0);
   return even.length==1? even[0] : odd[0];
 }

关键问题：自己在解决问题的时候不会优先想到数组的方法，filter，forEach，map，reduce。