The use of Creative Commons licenses for software is not recommended. The CC licenses do not address concerns specific to software (such as the source code/object code relationship, or patent issues), and are incompatible with most open-source software licenses.
If you want to license your software "with no conditions or rules", you probably want either:
"Releasing into the public domain" has the problem that not all jurisdictions permit you to simply abandon your copyright to a work; to get around this, CC-0 and WTFPL both retain copyright while relinquishing all rights to the greatest extent permissible by law; of the two, CC-0 is probably the better written.
If you want to retain the requirement of being attributed for your work, you want one of the highly-permissive licenses such as the three-clause BSD license or the MIT license. These are similar to CC-BY, but are designed for the needs of software.