Introduction - If you have any usage issues, please Google them yourself
Decimal to hexadecimal conversion. Requirements: 1. To obtain a decimal number from the keyboard and then the hexadecimal display on the screen 2. Able to continuously convert input decimal number to Enter the end of a decimal number as input 3. If the keyboard input is not a number, then the on screen prompts: " the input is not aa number, again, please!" 4. Typing ' q' key you can exit the program