fibonacci.js

   1 const Benchmark = require('benny')
   2
   3 const number = 30
   4
   5 /**
   6  * @param num
   7  * @returns
   8  */
   9 function fibonacciLoop (num) {
  10   const fib = []
  11   fib[0] = 0
  12   fib[1] = 1
  13   for (let i = 2; i <= num; i++) {
  14     fib[i] = fib[i - 2] + fib[i - 1]
  15   }
  16   return fib[num]
  17 }
  18
  19 /**
  20  * @param num
  21  * @returns
  22  */
  23 function fibonacciRecursion (num) {
  24   if (num <= 1) return num
  25   return fibonacciRecursion(num - 1) + fibonacciRecursion(num - 2)
  26 }
  27
  28 /**
  29  * @param num
  30  * @param memo
  31  * @returns
  32  */
  33 function fibonacciRecursionMemoization (num, memo) {
  34   memo = memo || {}
  35
  36   if (memo[num]) return memo[num]
  37   if (num <= 1) return num
  38
  39   return (memo[num] =
  40     fibonacciRecursionMemoization(num - 1, memo) +
  41     fibonacciRecursionMemoization(num - 2, memo))
  42 }
  43
  44 Benchmark.suite(
  45   `Fibonacci number ${number}`,
  46   Benchmark.add('fibonacciLoop', () => {
  47     fibonacciLoop(number)
  48   }),
  49   Benchmark.add('fibonacciRecursion', () => {
  50     fibonacciRecursion(number)
  51   }),
  52   Benchmark.add('fibonacciRecursionMemoization', () => {
  53     fibonacciRecursionMemoization(number)
  54   }),
  55   Benchmark.cycle(),
  56   Benchmark.complete(),
  57   Benchmark.save({ file: 'fibonacci', format: 'json', details: true }),
  58   Benchmark.save({ file: 'fibonacci', format: 'chart.html', details: true }),
  59   Benchmark.save({ file: 'fibonacci', format: 'table.html', details: true })
  60 ).catch(err => {
  61   console.error(err)
  62 })