input: Write a python function to merge two sorted arrays.
  assert mergeSortedArrays([3, 5, 7], [1, 2, 4]) == [1, 2, 3, 4, 5, 7]
  assert mergeSortedArrays([1, 3, 5], [2, 4, 6]) == [1, 2, 3, 4, 5, 6]
  assert mergeSortedArrays([], [1, 2, 3]) == [1, 2, 3]
  assert mergeSortedArrays([1, 2, 3], []) == [1, 2, 3]
  assert mergeSortedArrays([1, 2, 3], [4, 5, 6]) == [1, 2, 3, 4, 5, 6]
output: def mergeSortedArrays(arr1, arr2):
      i, j = 0, 0
      merged = []
      while i < arr1.length and j < arr2.length:
          if arr1[i] < arr2[j]:
              merged.append(arr1[i])
              i += 1
          else:
              merged.append(arr2[j])
              j += 1
      while i < arr1.length:
          merged.append(arr1[i])
          i += 1
      while j < arr2.length:
          merged.append(arr2[j])
          j += 1
      return merged