I'm writing a program where 10 values are entered and then the max, min, and mean of the user entered values are displayed.

Now i need to add a part where if the user does not want to enter 10 values, they can just press the enter key and 10 defined numbers that i make will be used instead.

What I need help with is how to check if the user only presses the enter key. I've never done this before considering i am in basic c programming and i don't know where to start. If anyone can help me out it'd be greatly appreciated.

Thanks