DSA · Theory

Sort an Array in Wave Form

Theory

605/810

Isha only reaches for Sort an Array in Wave Form when names A→Z has to stay correct in the roll list.

Sort an Array in Wave Form order — meaning → n log n vs n² → one limit. Dumping ten features helps nobody.

Without Sort an Array in Wave Form, the roll list gets messy and names A→Z is hard to trust.

Sort an Array in Wave Form shows up in the roll list. Name names A→Z, not “a real-world scenario”.

Sort an Array in Wave Form miss — unstable sort when equal keys matter. Fix it before you talk about advanced DSA.

After Sort an Array in Wave Form, Isha should still remember unstable sort when equal keys matter.

One breath for Sort an Array in Wave Form, then names A→Z, then unstable sort when equal keys matter. Sit down.

Diagram

  index →  0    1    2
  array → [10,  20,  30]

Exam tip

For Sort an Array in Wave Form: definition + the roll list + one failure.

arr = [10, 20, 30, 40]
print(arr[2], arr[-1])
matrix = [[1, 2], [3, 4]]
print(matrix[1][0])  # 3

Sort an Array in Wave Form — arrays give O(1) index access; matrices are arrays of arrays.