Read input from console in Ruby

puts "Enter A"
a = gets.chomp
puts "Enter B"
b = gets.chomp
c = Integer(a) + Integer(b)
puts c

you can also pass the parameters through the command line. Command line arguments are stores in the array ARGV. so ARGV[0] is the first number and ARGV[1] the second number
#!/usr/bin/ruby

first_number = ARGV[0].to_i
second_number = ARGV[1].to_i

puts first_number + second_number
and you call it like this
% ./plus.rb 5 6
==> 11