gimmeTriplet.js

// As a part of this Kata, you need to create a function that when provided with a triplet, returns the index of the numerical element that lies between the other two elements.

// The input to the function will be an array of three distinct numbers (Haskell: a tuple).

// For example:

// gimme([2, 3, 1]) => 0
// 2 is the number that fits between 1 and 3 and the index of 2 in the input array is 0.

// Another example (just to make sure it is clear):

// gimme([5, 10, 14]) => 1
// 10 is the number that fits between 5 and 14 and the index of 10 in the input array is 1.

function gimme (triplet) {
  const min = Math.min(...triplet)
  const max = Math.max(...triplet)

  const middleNum = triplet.filter(x => x !== min && x !== max)

  return triplet.indexOf(...middleNum)

}