How to bind conditions within c language if

if(num1 != 0)

can be coded as if(num1).

See https://www.le.ac.uk/users/rjm1/cotter/page_37.htm

I don't think I can understand the conditional expression properly because the sauce is getting longer.

After refectoring the source, understand the conditional expression again, and if it doesn't work, please attach how the variables above are manipulated.

I don't understand the question.

The above code is calculated as (num1!=0&&&num2!==0&&num1=num2) Two conditional expressions are calculated as ||

if ((num1 != 0 && num2 != 0 && num1 == num2) || (num1 != 0 && num2 != 0 && num1 == num2)) {}

This and

if ((num1 != 0 && num2 != 0 && num1 == num2)) {}

Is there a difference in this?

And the conditional expression above is

num1=1, num2=1 satisfies the condition.
After all, if num1, num2 is not 0 and is not 0, the condition is satisfied.