As I can see there isn't any fault in your C code. You're probably lacking some knowledge about your IDE (Turbo C++). Turbo C++ 3.0 on Windows 7 is really unimaginable. However, if you want to do this you should set your environment of Turbo C++. Take these simple steps:
- Go to the Menu Bar and click on Options
- Now Click on Linker and
- Choose libraries, Select the Graphic libraries
Since you are using it on Windows 7, it won't support full screen mode you should disable it. To do so, go to Environment and set source tracking to 'Current Window', which has a radio button swap it with 'New Window'.
For fullscreen mode support, you can download DOSBOX app. It can even run your old DOS applications.
For this you have to install DOSBOX and you need to mount your working directory.