Nodejs Fibonacci Sequence Get naiveFib()

Method Source Code

/**/*w  w w  .  j av  a  2  s  . com*/
 * Returns the Nth fibonacci number.
 * @extends Number
 * @function naiveFib
 * @return {number}
 *
 * Examples:
 *     Number(10).naiveFib();
 *     => 55
 */
Number.prototype.naiveFib = function () {
  if (Number(this) < 0)
    return -1;
  switch (Number(this)) {
    case 0:
      return 0;
    case 1:
      return 1;
    default:
      return (this-1).naiveFib() + (this-2).naiveFib();
  }
}

Related

1. iterFib()

   Number.prototype.iterFib = function () {
     var v1 = 0, v2 = 1, temp = 0;
     (new Array()).rangeArray(0, this-1).forEach(function(index) {
       temp = v2;
       v2 = v2 + v1;
       v1 = temp;
     });
     return v2;
   

2. memoFib(hash=})

   Number.prototype.memoFib = function (hash={}) {
     if (Number(this) < 0) return -1;
     else if (Number(this) === 0) return 0;
     else if (Number(this) === 1) return 1;
     else {
       prevFib = hash[this-1] || (hash[this-1] = (this-1).memoFib(hash));
       prevPrevFib = hash[this-2] || (hash[this-2] = (this-2).memoFib(hash));
       return prevFib + prevPrevFib;
   

3. sumFibs(num)

   Array.prototype.last = function() {
     return this[this.length-1];
   };
   Array.prototype.secondToLast = function() {
     return this[this.length-2];
   };
   function sumFibs(num) {
     var sequence = [1,1];
     while (sequence.secondToLast() + sequence.last() <= num) {
   ...