15. Recursion vs. Iteration

Any problem solvable with recursion can also be solved iteratively (using loops like for or while).

Iteration (Loops)

• Mechanism: Uses loops and updates state variables explicitly.
• Pros: Generally faster execution, better memory usage (no deep function call stack).
• Cons: Can sometimes be verbose or complex for inherently recursive problems (like tree manipulation).

Recursion

• Mechanism: Uses the function call stack implicitly to manage state.
• Pros: Often leads to simpler, more elegant, and highly readable code for certain types of problems.
• Cons: Slower due to function call overhead, and high space complexity due to using the call stack (can cause stack overflow if too deep).

When to use which? If the problem has a naturally recursive structure (e.g., fractal generation, tree traversal), recursion is usually preferred for clarity. Otherwise, iteration is typically more performant.