Take a number input, iterate up to the top of a given range and output numbers into a file

I'm hoping to get my Ruby script to start at an inputted number, say 100, and itterate all the way up to the end of the range; 1000. Having all the numbers in between saved to a file.

This is a code I have so far:

#!/usr/bin/env ruby

if ARGV.length ==0; 
 puts "Enter the start number"
 else puts ARGV.size  
ARGV.each do |a| 


for i in 0..1000 do
 puts i;

     end  
 end
end

To run it I'm typing:

ruby increment.rb 100 > increment.txt 

However, it ignores the input number and starts at 1开发者_开发问答 regardless.

What am I doing wrong?

It starts at 0 because you're giving it the range 0..1000, which starts at 0. If you want to use the numeric value of a as the starting point, use a.to_i instead of 0.

ARGV is an array and the first argument is stored in ARGV[0] second in ARGV[1] etc

if ARGV[0]
  start = ARGV[0].to_i
else
  puts "Enter the start number"
  start = gets.to_i
end

(start .. 1000).each do |i|
  puts i
end