# Cel2FahrWithValidation Example
# Convert a Celsius temperature to Fahrenheit.
# Don't allow input temperatures less than absolute zero (-273 degrees C). 

import sys
cel = input("Enter a Celsius temperature: ")
if cel < -273.0
    print("Input temperature cannot be less than absolute zero.")
    sys.exit( )

fahr = 9.0 * cel / 5.0 + 32.0
print(f"The corresponding Fahrenheit temperature is {fahr}.")