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Recursion

Medium

In plain terms

Recursion is when a function calls itself. Need a base case to stop. Used for trees, factorial, Fibonacci. Can cause stack overflow for deep recursion.

What you need to know

  • •Function calls itself
  • •Base case
  • •Call stack depth

Try it yourself

Copy the code below and run it in your browser console or a code editor:

function factorial(n) {
  if (n <= 1) return 1;
  return n * factorial(n - 1);
}

function fib(n) {
  if (n <= 1) return n;
  return fib(n - 1) + fib(n - 2);
}

Learn more

Dive deeper with these trusted resources:

MDNjavascript.infoTutorialsPointW3Schools