validityChecker

validityChecker1 = arr => {
  'use-strict'

  const printDistance = (x1, y1, x2, y2) => {
    let distance = Math.sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2)
    console.log(`{${x1}, ${y1}} to {${x2}, ${y2}} is ${Number.isInteger(distance) ? 'valid' : 'invalid'}`)
  }

  printDistance(arr[0], arr[1], 0, 0)
  printDistance(arr[2], arr[3], 0, 0)
  printDistance(arr[0], arr[1], arr[2], arr[3])
}