function swapPairs(nums: number[]): number[] {
  let newArray = []
  for (let i = 0; i < nums.length - 1; i += 2) {
    newArray.push(nums[i+1])
    newArray.push(nums[i])
  }
  if(nums.length % 2 != 0) newArray.push(nums.length)
  return newArray;
}

// No modificar: necesario para evaluar el resultado.
export { swapPairs };