Ruby 斐波那契乘法 Table

Question

Ruby斐波那契乘法Table这是一道面试题。

最近开始从事软件开发，遇到了这个挑战。你能告诉我下面，我如何用 Ruby 语言写斐波那契乘法 table 吗？在过去的几天里，我一直在尝试实现它，但似乎我面临着一堵砖墙，代码让我感到疯狂，而且我在面试中失败了，但目前这并不重要。我将不胜感激任何帮助。非常感谢。

应用程序控制器：

class ApplicationController < Sinatra::Base

    configure do
        set :public_folder, 'public'
        set :views, 'app/views'
    end
    
    get '/' do
        @time_of_day = Time.now
        erb :index
    end
    
end

斐波那契控制器：

class FibonacciController < ApplicationController

    get '/fibonacci' do
        place = params[:place].to_i
        @sequence = fib(place)
        erb :fibonacci
    end

    def fib(place)
        res = []
        a = 0
        b = 1
        
        while b < place do
        res << b         
        a,b = b,a+b
        end
        
        res 
    end

end

Fibonacci.erb

<div class="container">
<h1> Fibonacci sequence: </h1>
    <div class="sub-container">
        <p> Generated fibonacci sequence: </p> 
        <%= @sequence.join(', ') %>
    </div>  
</div>

Index.erb

<div class="container">
    Date and time: <%= @time_of_day %>
    <br>
    <h1> Fibonacci Multiplication Table </h1>
    <p> Enter your number below: </p>

    <form method="GET" action="/fibonacci">
        <label for="sequence">
        <input type="integer" name="place" placeholder="Insert your number">
        <input type="submit">
    </form>
    
</div>

（这是本次挑战的最终目标）

Answer 1

FibonacciController 代码

class FibonacciController < ApplicationController

  get '/fibonacci' do
    place = params[:place].to_i
    sequence = fib(place)
    @table = generate_table(sequence)
    erb :fibonacci
  end

  def fib(place)
    return [] if place <= 0

    a = 0
    b = 1
    res = [a]

    while res.length < place do
      res << b
      a,b = b, a+b
    end

    res 
  end

  def generate_table(sequence)
    return [] if sequence.length.zero?

    cols = []
    (sequence.length + 1).times do |row|
      row_data = []
      (sequence.length + 1).times do |col|
        row_data << generate_table_element(row, col, sequence)
      end
      cols << row_data
    end
    cols
  end

  def generate_table_element(row, col, sequence)
    return '_' if row.zero? && col.zero?
    return sequence[col - 1] if row.zero?
    return sequence[row - 1] if col.zero?

    sequence[col - 1] * sequence[row - 1]
  end

end

并且在 erb 文件中

<p> Generated fibonacci sequence: </p> 
<% @table.each do |table_row| %>
  <%= table_row.join(',') %>
  <br/>
<% end %>

Ruby 斐波那契乘法 Table

Ruby Fibonacci Multiplication Table

ruby

fibonacci

sinatra