Thread: If Then Statments

Originally posted by BladeBoss2
I don't understand IF, THEN statments and also I don't get the Boolean operators OR, NOT, and AND.

I've read the turtorial about them but I just don't understand them and i don't get this:

A. !(1 || 0) ANSWER: 0
B. !(1 || 1 && 0) ANSWER: 0 (AND is evaluated before OR)
C. !((1 || 0) && 0) ANSWER: 1 (Parenthesis are useful

Can someone please help me out with this?

What's not to understand? There is no "THEN" in C.

if ( this_is_non_zero ) /* then do something */

Thus:

a OR b == If 'a' or 'b' is non zero, then...
!( a OR B) == reverse the answer from the "a or b" comparison.

SO, in this case, since 1 is one, then the OR comparison is true. Since you reverse the answer, it becomes false.

Anything "AND ZERO" is false. Thus, it goes to reason, that the opposite of zero is true, so the "!( .. AND ZERO )" will equate to true.

Quzah.

You do realise that the exclamation mark is used to reverse the result? So

!(1 OR 0) wouldn't the answer be 1 OR 0 ? why is it 0 ?

We start with 1 OR 0, which equates to 1. Then it's reversed using the ! symbol, so the answer is 0.

Apply this to the others and see if you understand better.

! is a NOT symbol, btw.

!((1 || 0) && 0) ANSWER:1

- (1 || 0) means 1 OR 0, result: 1

so now it looks like this

>!(1 && 0)

Now we go
- 1 && 0 means 1 AND 0, result: 0

so now it looks like this

>!(0)

This means NOT (0), result: 1

Remember the brackets restrict and control the order in which things happen.