"Zexu Ding" [email protected] wrote:

Do I need to consider the possible mismatched brackets? Like:

func((1+2, foo)

You wouldn't need to check mismatched brackets as Chris said expression checking isn't necessary.

Am I supposed to use %d or %f according to the different return values of the expression?

Yes, if 24.00, print as 24. if 24.5, print as 24.500000

And what is the maximum recursive depth of the expression?

print (  (func(1, (2 + 3) * 2.9, func1(2) + func2())) )

printf("%d", func(1, (2 + 3) * 2.9, func1(2) + func2()));

Not sure but better to be safe than sorry and assume it can be as deep as it is in C.