Q.

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)

A)

function findOutlier(integers){
  let oddNumbers = integers.filter(el => el % 2 !== 0);
  
  if (oddNumbers.length === 1) {
    const [result] = oddNumbers;
    return result;
  }
  else {
    let evenNumbers = integers.filter(el => el % 2 === 0);
    const [result] = evenNumbers;
    return result;
  }
}

other

굳이 구조분해할당으로 안 해도 어차피 1개 밖에 없으니까 0번 인덱스로 접근해도 될 것을!

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