Mistake

Question

Where is the mistake?
int a=3;
if (a>0)b=a*a;
int c = a+b;

Answer 1

It would be easier to say what was NOT a mistake than to list the mistakes.

What specifically is this code supposed to do?

Where's the rest of it?

Answer 2

What about this: ( free interpretation of your code)

a=3;
if (a>0):
b=a*a
c = a+b
print(f'a = {a}, b = {b}, c = {c}')

Answer 3

You didn't specify a language in the tags, that's the mistake ; )

Answer 4

With about 12 languages in solo learn which are almost similar in terms of their syntax, putting a code like yours and not specifying what language it is written on makes it rather difficult to assist you. Otherwise the issue is with the main() and the return 0; that is if we are talking c++