fibonacci recursion javascript code example

Example 1: fibonacci javascript

function Fibonacci(num){
	var before = 0;
	var actual = 1;
	var next = 1;

	for(let i = 0; i < num; i++){
		console.log(next)
		before = actual + next;
		actual = next
		next = before
	}
}

Fibonacci(100);

Example 2: 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 3: js fibonacci sequence

// number fibonnaci to array format
function fibonacci(nums) {
  
  let fib = [0, 1];
  let data = [];
  
  for(let i = 2; i <= nums; i++) {
    fib[i] = fib[i - 1] + fib[i - 2]; 
    data.push(fib[i]);
  }
  
  return data;
}

Example 4: javascript fibonacci

function fibonacci(n) {
   return n < 1 ? 0
        : n <= 2 ? 1
        : fibonacci(n - 1) + fibonacci(n - 2);
}

console.log(fibonacci(4));

Example 5: fibonacci best performance javascript

// A sequência começa com 0 e 1, depois,
// os números subsequentes são compostos
// pela soma dos dois números anteriores
// da sequência. Daí:
// (x - 2) + (x - 1) = próximo número da sequência
function fibonacci(n) {
	const list = [0, 1];
	for (let x = 2; x < n + 1; x += 1) {
		list.push(list[x - 2] + list[x - 1]);
	}
	return list[n];
}

console.log(fibonacci(4));

Example 6: fibonacci recursion javascript

function fibonacci(n) {
    if (n < 2){
        return 1;
    }else{
        return fibonacci(n-2) + fibonacci(n-1);
    }
}

console.log(fibonacci(7));
//Returns 21