Algorithms From Scratch

A growing collection of classic algorithms implemented from scratch in Kotlin. Each entry includes a runnable example and brief notes on behavior and complexity. The current entry point is src/Main.kt.

Algorithms

Binary Search (implemented)

• Operates on a sorted array with two pointers (left, right) bracketing the search range.
• Repeatedly checks the middle index mid = (left + right) / 2; if the middle value is greater than the target, it discards the right half, if less, it discards the left half. This halves the search space each step.
• Stops when the target is found (returns its index) or the range is exhausted (returns -1).
• Complexity:
  • time: $O(log \times n)$ because the range halves on each iteration;
  • space: $O(1)$ because only a few index variables are tracked.