Question

I know, boolean variables are NO by default.

BOOL first;
BOOL second;

if (first != second) {
    NSLog(@"Yes");
}else{
NSLog(@"NO");
}

The OutPut is :Yes

But when i assign NO to first and second, i got ‘NO’ out put.

first = NO;
second = NO;

if (first != second) {
    NSLog(@"Yes");
}else{
NSLog(@"NO");
}

The OutPut is: NO

Where is the problem? Or should boolean variables exactly take NO by default? Or Depending on compiler?

I have used Xcode 4.2 version. I don’t understand where the problem is. Please explain any one with example. Thanks in advance.

Answer 1

Local variables are not initialized by default; you get random garbage in them. You should initialize them with BOOL first = NO; if you want them to have a reasonable value.