Checkerboard Pattern

Create a function that returns true if the two-dimensional n x n input array has a checker-board pattern.

Examples

isCheckerboard([
  [1, 1],
  [0, 1]
]) ➞ false

isCheckerboard([
  [0, 1],
  [1, 0]
]) ➞ true

isCheckerboard([
  [1, 0, 1, 0, 1],
  [0, 1, 0, 1, 0],
  [1, 0, 1, 0, 1],
  [0, 1, 0, 1, 0],
  [1, 0, 1, 1, 1]
]) ➞ false

isCheckerboard([
  [1, 0, 1, 0, 1],
  [0, 1, 0, 1, 0],
  [1, 0, 1, 0, 1],
  [0, 1, 0, 1, 0],
  [1, 0, 1, 0, 1]
]) ➞ true

Notes

• An element in the array adheres to the checker-board pattern if the elements directly to the left, right, top and below are of a different type, and the elements on the diagonal direction are of the same type.
• The element in the upper-left corner can be either 0 or 1.