duanfeiqu1989 2013-07-11 22:02 采纳率: 100%
浏览 16
已采纳

转到斐波那契数列生成器

This is my fibonacci generator:

package main

import "fmt"

func main() {
    for i, j := 0, 1; j < 100; i, j = i+j,i {
        fmt.Println(i)
    }
}

It's working, but I don't know how can I improve it, I'd like more expert approaches about it, Thanks...

  • 写回答

1条回答 默认 最新

  • dongxie5698 2013-07-11 22:15
    关注

    I assume you are talking about improving the time complexity (and not the code complexity).

    Your solution computes the Fibonacci numbers in O(n) time. Interestingly, there exists an O(log n) solution as well.

    The algorithm is simple enough: Find the nth power of matrix A using a Divide and Conquer approach and report (0,0)th element, where

     A = |1     1 |
         |1     0 |
    

    The recursion being

     A^n = A^(n/2) * A^(n/2)
    

    Time complexity:

    T(n) = T(n/2) + O(1) = O(logn)
    

    If you think about it with a piece of paper, you'd find that the proof is simple and is based upon the principle of induction. If you still need help, refer to this link

    NOTE: Of course, the O(logn) time is true only if you want to find the nth Fibonacci number. If, however, you intend to print ALL of the n fib numbers, theoretically, you can not have a better time complexity than you already have.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

报告相同问题?