Newbie Trouble

[Phack]

Hello, im in the process of teaching myself PERL from a book. I have a background in VB, so it is going fairly easy for me, so far.... As one of the excercises in the book, there is a program i had to write to find prime numbers, but i cannot figure out why it wont run properly? I would greatly appreciate your help on this. Im trying to do the best i can with just this book i have, but i seem to constantly hit a roadblock. heres the code, please examine, yeah, its pathetic)


#!/usr/bin/perl -w

$maxprimes=20;
$value=1;
$count= 0;
While($count < $maxprimes) {
$value++;
$composite=0;
OUTER: for ($i=2; $i<$value; $i++) {
for($j=$i+; $j<$value; $j++) {
if (($j*$i)==$value) {
$composite = 1;
last OUTER;
}
}
}
if (! $composite) {
$count++;
print &quot;$value is prime\n&quot;;
}
}

 

[TopMach]

&quot;it is going fairly easy for me, so far...&quot;. &quot;i seem to constantly hit a roadblock&quot;. Sounds paradoxal to me.

 

[PaulTEG]

#!/usr/bin/perl -w

$maxprimes=20;
$value=1;
$count= 0;
While($count < $maxprimes) {
$value++;
$composite=0;
OUTER: for ($i=2; $i<$value; $i++) {
for($j=$i+; $j<$value; $j++) {
if (($j*$i)==$value) {
$composite = 1;
last OUTER;
}
}
}
if (! $composite) {
$count++;
print &quot;$value is prime\n&quot;;
}
}

while - lower case w
$i+1 rather than $i+, definitely not $i++ cos then you'll affect $i in the outer loop

Seems to work, except it's saying 49 is prime

HTH
Paul

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