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blindguyinanorg
14-02-2004, 19:40
simple question, in an if statement is a value of 0 = to false or to i need to say !variable==0 to get false( or variable==1). not too important it will just save me time in writing the code and i dont want to go back and have to fix it.

kiracofe8
14-02-2004, 20:00
simple question, in an if statement is a value of 0 = to false or to i need to say !variable==0 to get false( or variable==1). not too important it will just save me time in writing the code and i dont want to go back and have to fix it.

int x = 0;
if (x)
//this code never executes
else
//this code always excutes


However, in C, I would consider it to be good coding practice to explicitly write the test as:

if (x == 0)
// stuff
else
// other stuff

or even

if (x != 0)
//other stuff
else
//stuff.

Ryan M.
15-02-2004, 07:31
Just to clarify what he said, in C any non-zero value is true. Zero is false. So, if you had a variable and you wanted to test if it was zero, you could say:

if(!variableBeingTested)
{
// Variable is zero
}
else
{
// Variable is not zero
}

It is considered better form by most people, however to explicitly put in the test for zero. For example:

if(variableBeingTested == 0)
{
// Variable is zero
}
else
{
// Variable is not zero
}

--EDIT--
PS I just looked at the last post guy's name and team number and realized he's one of my team's mentors. :)