Recursive Fibonacci in Javascript

Skills used and tools used: #Javascript, #Algorithms, #HTML, #Jekyll, #jQuery, and #CSS

Written by Tyler La Fronz on February 7, 2018

The Fundamentals

At its core, a basic Fibonacci algorithm is incredibly slow and inefficient. This implementation of Fibonacci includes a data structure to memorize previously calculated numbers in the sequence.

Please enter a value:

The function that computes this

var memo = [0, 1]; //Stores the previously calculated values

function fib(fibNum) {
  var result = 0;
  if (memo[fibNum]) { //Checks for previously calculated value
    result = memo[fibNum]; //returns the value stored
  } else if (fibNum >= 2) {
    result = fib(fibNum - 1) + fib(fibNum - 2); //recursively calls for the value
    memo[fibNum] = result; //Stores the result
  }
  return result; //returns the value
}