fibonacci numbers recursion javascript code example

Example 1: javascript recursive fibonacci

// Recursion way to return Fibonacci numbers
function recursiveFibonacci(n){
	// base case
	if(n === 0) return 0
  	if(n === 1) return 1
  
  	// recursioin base
  	return recursiveFibonacci(n - 2) + recursiveFibonacci(n - 1);
}
recursiveFibonacci(6) // should return 8

//////// and ////////

// Iteration way to return Fibonacci numbers
function iterativeFibonacci(n) {
  if (n === 0) return 0;
  if (n === 1) return 1;

  let previous = 0;
  let current = 1;
  for (let i = n; i > 1; i--) {
    let next = previous + current;
    previous = current;
    current = next;
  }
  return current;
}

iterativeFibonacci(6) // should return 8

Example 2: recursive function for fibonacci series in java javascript

var fib = function(n) {
  if (n === 1) {
    return [0, 1];
  } else {
    var arr = fib(n - 1);
    arr.push(arr[arr.length - 1] + arr[arr.length - 2]);
    return arr;
  }
};

console.log(fib(2));