From: Giampiero Zanchi <cidza@...>
Date: 2012-02-09T21:18:14+09:00
Subject: Re: Range in a loop

hello

this is simple; you could try yourself

anyway...

def odd_even_numbers n # this function calculates next number in the 
sequence
 if n % 2 == 0 # identifies even number
   return n / 2 # even number is divided by two
 else
   return n * 3+1 # odd number is multiplied by three plus one
 end
end

print "Give me two numbers (blank separated): "
num1, num2 = gets.chop.split(" ").map {|x| x.to_i } # changes into 
integers, reads it
max_seq = 0 ; max_seq_num = 0
num1.upto(num2) do |num|
  n = num
  counter = 1
  while n > 1 # stops when it reaches number one
    n = odd_even_numbers(n)
    counter += 1
  end
  if counter > max_seq
    max_seq = counter
    max_seq_num = num
  end
end

puts "Max seq lenght: #{max_seq}"
puts "Max seq num: #{max_seq_num}"

add controls, for instance to be sure that 2 numbers in input, num1 < 
num2, and so on

-- 
Posted via http://www.ruby-forum.com/.