is there a problem with...

for ( n = 1; n =< 150; n++; )
this line of code?
I continuosly get a syntax error with this line and can find no problem with it. Thank you in advance.

A for loop only takes 4 parameters, you’ve got an extra ‘;’ at the end. It should be

for (n = 1; n =< 150; n++)

Err … aside from the mentioned extra semicolon at the end, unless my memory has become severly skewed, I do believe you mean “<=” for less than or equal to, as opposed to “=<”. But why such wird code? I mean, really, who starts counting at 1? (Besides normal people, of course :wink:

Traditionally, though, you’d say

for (n=0; n < 150; n++)

This is because C starts indexing at 0, like most sane languages. You can also avoid having an equal sign in the for loop. I suppose it is a matter of taste, though … (and what you do with n within the loop)

and do make sure that you’ve declared ‘n’ as well :slight_smile: but the main problems are probably those already pointed out, i.e. it should be <=, and there should only be 2 semicolons.

I hope you meant “3” parameters, not 4 :slight_smile:

just thought I would emphasize on this for the n00bs.

 for (n = 0; n <= 150; n++)
 // For statements are a type of loop for exuting a snipet of until 
 // it evalueates to false. In the above statement the structure goes 
 // as follows. The first part is the intial variable settings before 
 // looping, the secound part is the testing part, and the third part is 
 // what to do after every loop. 

// The following example will loop 150 times before evaluating to false 
// or 0 ending the loop. 

// code

another variation
n = 0

while(n <= 150)
// Simular to the above statement except that this uses a "global" 
// variable which can be called other places in the program. 

// code


Oh boy, that’s what I get for trying to do work and read CD at the same time. Hopefully I didn’t make such stupid mistakes on my real code :ahh:

Yes, I meant ‘3’ instead of ‘4’ and I guess I also missed the ‘=<’. Sorry, and thanks for noticing my mistakes.

One of your comments is off. Your for loop in C:

for ( n = 0; n <= 150; n++)

will do this:
-set n to zero, run code once
-go back to the for statement, add 1, is n <= 150? yes, so run code twice
-(n is now 150) go back to the for statement, add 1, is n <= 150? no, so stop.

The loop will run 151 times, NOT 150 times. Think of a simpler for loop:

for ( n = 0; n <= 2; n++)

n = 0, execute loop.
n = 1, execute loop,
n = 2, execute loop,
n = 3, stop.

If you start at zero and go to 2, the loop runs 3 times - the final valid number, plus one.

Which is why you typically see for (n = 0; n < 150; n++) instead.

The same reasoning applies to the lower for statement.

-Brandon Heller