A Simple Dance

You will be given an array of dancing couples, with the woman first and man second, as well as a parameter "men" or "women".

• If the parameter is "men", the men reverse their positions (first moves to last, last moves to first, etc), while women keep their positions.
• If the parameter is "women", the women reverse their positions, while men keep their positions.

Examples

dance([
  [Ana, Bob],
  [Amy, Josh],
  [Lisa, Tim]
], men) ➞ [
  [Ana, Tim],
  [Amy, Josh],
  [Lisa, Bob]
]

dance([
  [Ana, Bob],
  [Amy, Josh],
  [Lisa, Tim]
], women) ➞ [
  [Lisa, Bob],
  [Amy, Josh],
  [Ana, Tim]
]

Notes

Input arrays will always be the same length.