Diagonal Rug

Create a function that takes in size and direction and generates a diagonal rug.

The size is the n parameter, and all rugs are square n x n. The direction is whether the diagonal part begins on the left or the right side.

Examples

generate_rug(4, "left") ➞ [
  [0, 1, 2, 3],
  [1, 0, 1, 2],
  [2, 1, 0, 1],
  [3, 2, 1, 0]
]

generate_rug(5, "right") ➞ [
  [4, 3, 2, 1, 0],
  [3, 2, 1, 0, 1],
  [2, 1, 0, 1, 2],
  [1, 0, 1, 2, 3],
  [0, 1, 2, 3, 4]
]

generate_rug(1, "left") ➞ [
  [0]
]

generate_rug(2, "right") ➞ [
  [1, 0],
  [0, 1]
]

Notes

• n > 0
• A 1 x 1 rug is trivially [[0]] (same for left and right).