Heeyz need a bit of help

got these 2 codings

PHP Code:

$score = "21700";
$scorepre = $score*2;
echo $scorepre . "<br>";
for($c=0;$c<strlen($scorepre);$c++) {
@$realscorecheck+=$scorepre{$c}*($c+1);
@$realscorecheck-="1";
}
echo $realscorecheck; 


PHP Code:

$score = "43400";
$scorepre = $score;
echo $scorepre . "<br>";
for($c=0;$c<strlen($scorepre);$c++) {
@$realscorecheck+=$scorepre{$c}*($c+1);
@$realscorecheck-="1";
}
echo $realscorecheck; 


the first one returns -5
And the second one 17
Don't get it why are they different? I've been looking at this for a while but don't see anything.

Must be something i'm overlooking
Hope you see it..


Greetz
Thierry

First of all, you should not be trying to multiply a string times two. If you want $score to be a number, don't use quotes. I honestly can't tell you what happens when you multiply a string.

PHP Code:

$score = 21700;
$scorepre = $score * 2; 


Secondly, don't try to check the length of a number. If $scorepre is a number, then cast it back to a string before you check it's length (as you do in the for loop definition).

PHP Code:

for($c=0;$c<strlen( (string) $scorepre);$c++) 


Lastly, I have no idea what this code is even supposed to be doing:

PHP Code:

$realscorecheck+=$scorepre{$c}*($c+1) 


What are you trying to do here? What effect will $scorepre{$c} have? Can you tell us what you are trying to compute?

well it's used for protecting my highscore list.
My flash program creates a checksum for the score.
And then the php should create a checksum and see if it matches the flash checksum.

Code looks like this

[PHP]$score = "21700";
$scorepre = $score*2;
echo $scorepre . "<br>";
for($c=0;$c<strlen($scorepre);$c++) {
@$realscorecheck+=$scorepre{$c}*($c+1);
@$realscorecheck-="1";
}
echo $realscorecheck;PHP] ///-5

PHP Code:

$score = "43400";
$scorepre = $score;
echo $scorepre . "<br>";
for($c=0;$c<strlen($scorepre);$c++) {
@$realscorecheck+=$scorepre{$c}*($c+1);
@$realscorecheck-="1";
}
echo $realscorecheck; 


///17


What i want to do is take each character in $scorepre and multiply the first one with 1 the second character with 2 the third one with 3 and so on. Then take 1 of per character.
And then ad all those results together.

Example:
43400 gives
(4*1-1)+(3*2-1)+(4*3-1)+(0*4-1)+(0*5-1)
3+5+11-1-1=17

The problem is i need to get the score and multiply it before doing above.
And for some reason 43400 gives the right number (17)
And 2*21700 gives -5

hmmz anybody???

well i finaly figured it out.