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。