#!/usr/bin/ruby

# f2c: 5*(F - 32)/9
# c2f: 9*C/5 + 32

degrees = ARGV[0]
current = degrees[0, degrees.length - 1].to_f
fc = degrees[-1,1]

if (fc == "f")
  converted = 5 * (current - 32) / 9
  puts "#{current}°F = #{converted}°C"
elsif (fc == "c") 
  converted = 9 * current / 5 + 32
  puts "#{current}°C = #{converted}°F"
else
  puts "ERROR: #{fc} is not a valid unit of measure."
end