Hi Monks,

I'm using a webshop program called hishop. Recently a discovered a bug. The problem is that when an article has a price of 17.95 and the quantity is 3 the program makes a multiplication error. The total should be 53.85, but the program gives 53.84. Using a price of 17.96, 17.94 or 10.95 gives the correct result.

The program uses a subprogram called round(), this is where it goes wrong. My knowledge of perl is not sufficient to find the error.

I made an example program. Please help.

Best regards, John Vanbeek 
 

#!/usr/bin/perl 

$price=17.95; 
$qtyx=3; 

$cost=round($price * $qtyx); 


$cost=commas($cost);$price=round($price);$price=commas($price); 

print "Content-type: text/html\n\n"; 

print "total costs are $cost"; 


sub round { 
my($fig)=@_; 
$fig=($fig * 100); 
if($fig=~/\./){ 
$fig=~m!^([0-9]*)\.([0-9])!;$fig=$1;$ext=$2; 
if($ext>4){$fig++;} 
} # end if($fig=~/\./); 
$fig=int($fig); if($fig=~/^[0-9][0-9]$/){$fig="0$fig";} 
$fig=~s!^([0-9]+)([0-9][0-9])$!\1\.\2!; 
if($fig eq '0'){$fig='0.00';} 
return($fig); 
} 
######################################################################
+####################### 
sub commas { my($fig)=@_; $fig=~s!\,!!g; 
my ($figx,$ext)=split(/\./,$fig); $ext=($ext)?"\.$ext":''; 
$figx=~s!^([0-9]+)([0-9]{3})$!\1\,\2!; 
while($figx=~/^([0-9]+)([0-9]{3})\,(.*?)$/){$figx=~s!^([0-9]+)([0-9]{3
+})\,(.*?)$!\1\,\2\,\3!;} 
$figx=($figx.$ext); 
return $figx; 
}

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