DEV Community

Cover image for πŸ” Recursion β€” Think Smaller to Solve Bigger
OneDev
OneDev

Posted on

πŸ” Recursion β€” Think Smaller to Solve Bigger

Recursion is when a function calls itself to solve a problem by breaking it down into smaller subproblems.

It’s everywhere β€” from algorithms to UI rendering.

πŸ“¦ Real-world examples:

  • File system traversal
  • DOM rendering in React
  • Tree/graph traversal
  • Backtracking problems (e.g. Sudoku, N-Queens)

🧠 Key idea:

Every recursive function should have:

  1. A base case β€” when to stop
  2. A recursive case β€” how to reduce the problem
function countDown(n) {
  if (n === 0) return;
  console.log(n);
  countDown(n - 1);
}
Enter fullscreen mode Exit fullscreen mode

🚨 Gotchas:

  • Recursion can be elegant, but deep recursion may lead to stack overflow.
  • Sometimes it's better to refactor to an iterative solution.

⚑ TL;DR

  • Recursion helps solve problems by thinking in terms of subproblems.
  • Just make sure it has a clear base case to avoid infinite loops.
  • It's powerful, but use it wisely β€” especially with large inputs.

πŸ’¬ Want a post with real coding problems that use recursion? Let me know!

Top comments (0)