#!/usr/local/bin/ruby -w

puts "Usage: fib.rb n1 [n2...]" if ARGV.empty?

# Returns the n-th fibonacci number
def fib(n)
    a, b = 0, 1
    n.times do
        a, b = b, a+b
    end
    return a
end

ARGV.each do |n|
    puts "The #{n}th Fibonacci number is #{fib(n.to_i)}."
end