Discussion on: Daily Challenge #117 - MinMinMax

[Kiliman]

TypeScript with tests

github.com/kiliman/dev-to-daily-ch...

export const minMinMax = (
  set: number[],
): [number, number | undefined, number] => {
  if (set.length < 1) {
    throw new Error('set must include at least one number')
  }
  const sorted = [...set].sort((a, b) => a - b)
  const smallest = sorted[0]
  const largest = sorted[set.length - 1]
  let minimumAbsent = smallest + 1
  for (let i = 1; i < sorted.length; i++) {
    if (minimumAbsent !== sorted[i]) break
    minimumAbsent++
  }

  return [
    smallest,
    minimumAbsent > largest ? undefined : minimumAbsent,
    largest,
  ]
}

Test

import { minMinMax } from '.'

it('should throw an error if less than one element', () => {
  expect(() => minMinMax([])).toThrow()
})

it('should return smallest, minimumAbsent, largest from array of numbers', () => {
  expect(minMinMax([-1, 4, 5, -23, 24])).toStrictEqual([-23, -22, 24])
  expect(minMinMax([1, 3, -3, -2, 8, -1])).toStrictEqual([-3, 0, 8])
  expect(minMinMax([2, -4, 8, -5, 9, 7])).toStrictEqual([-5, -3, 9])
})

it('should return undefined for minimumAbsent if not present between smallest and largest', () => {
  expect(minMinMax([-3, -2, -1, 0, 1, 2, 3])).toStrictEqual([-3, undefined, 3])
})

it('should support a single number', () => {
  expect(minMinMax([1])).toStrictEqual([1, undefined, 1])
})

it('should support two numbers', () => {
  expect(minMinMax([1, 2])).toStrictEqual([1, undefined, 2])
  expect(minMinMax([1, 3])).toStrictEqual([1, 2, 3])
})