Adding 1 to array?

[spl1nter]

In one of my scripts I have this code:

PHP Code:

$set_num = 0;
while ( $answers[$set_num] != "" )
{
        if ( $answers[$set_num] == $actual_answer )
        {
             $results[$set_num]++;
        }
        $set_num++;
}
unset($set_num); 


Currently $answers[] contains 3 values but this may change depending on the results it pulls from the database earlier in the script.
As an example (because I'm not very good at explaining ):

$answers[0] = Yes;
$answers[1] = No;
$answers[2] = Don't know;

$results[0] = 2;
$results[1] = 7;
$results[2] = 3;

$actual_answer contains the data submitted by the user. Basically I want 1 to be added to one of the $results[] when the corresponding $answer[] is submitted. This script works for $result[0] and $result[1] but when the user selects the answer corresponding to $answers[2], $results[2] does not get 1 added to it's value.

Why does this happen and how can I fix it?

[LazyJim]

does result[2] definately contain a number?

[imaginemn]

Try:

$set_num = 0; 
while ( $answers[$set_num] != "" ) { 
        if ( $set_num == $actual_answer ) { 
		$new_value = $results[$set_num]+1; 
        } 
        $set_num++; 
} 
unset($set_num);

imaginemn

[littleFella]

yeah, that seems strange, although it happens in more than one language that an increment function won't kick in for some reason. I admit I''ve been looking at this and couldn't find a problem in code.

It almost looks as if the WHILE condition is not always seeing the right values so the loop breaks prematurely. If so then another approach could be the use of a FOR loop instead. At least you force the code to iterate a predefined number of times. The trick is that you may need to dynamically establish a number of iterations before jumping into the loop.

[imaginemn]

This one is a little tough because I do not know if $actual_answer is a number or a string. If it's a string I would probably use the strcmp(str1, str2) command instead.

In reality there is nothing wrong with the code that was submitted. I guess we would need to see the rest of the code because the function does work. I added a print command to see what was being displayed and in this example the first output is 3 and the second is 4.

$actual_answer = "Don't know";
$answers[0] = "Yes"; 
$answers[1] = "No";
$answers[2] = "Don't know";

$results[0] = "2";
$results[1] = "7";
$results[2] = "3";

$set_num = 0; 
while ( $answers[$set_num] != "" ) 
{ 
        if ( $answers[$set_num] == $actual_answer ) 
        { 
		print $results[$set_num];
		print "<BR>";

		$results[$set_num]++; 

		print $results[$set_num];
		print "<BR>";
        } 
        $set_num++; 
} 
unset($set_num);