Beefy Boxes and Bandwidth Generously Provided by pair Networks
Syntactic Confectionery Delight
 
PerlMonks  

Re^4: Prime Number Finder

by Anonymous Monk
on Sep 17, 2013 at 08:46 UTC ( #1054405=note: print w/ replies, xml ) Need Help??


in reply to Re^3: Prime Number Finder
in thread Prime Number Finder

This code is quite fast, since it skips a lot of unnecessary operations

#!/usr/bin/perl use strict; use warnings; use POSIX; my ($i,$j,$h,$sentinel) = (0,0,0,0); # i>=3 for($i=1000000000; $i<=1000000500; $i++){ # if $i is an even number, it can't be a prime if($i%2==0){} else{ $h=POSIX::floor(sqrt($i)); $sentinel=0; # since $i can't be even -> only divide by odd numbers for($j=3; $j<=$h; $j+=2){ if($i%$j==0){ $sentinel++; # $i is not a prime, we can get out of the loop $j=$h; } } if($sentinel==0){ print "$i \n"; } } }


Comment on Re^4: Prime Number Finder
Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1054405]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (6)
As of 2015-07-07 07:03 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (87 votes), past polls