Regex to match string with 3/4 sub pattern

Regex to match string with 3/4 sub pattern

References

Reference NO 1

http://docs.python.org/library/re.html

Reference NO 2

http://stackoverflow.com/questions/15197099/regex-to-match-string-with-3-4-sub-pattern

Reference NO 3

http://php.net/manual/en/function.preg-match.php

Reference NO 4

http://www.tutorialspoint.com/python/python_reg_expressions.htm

Reference NO 5

http://www.regular-expressions.info/rlanguage.html

Reference NO 6

http://www.javascriptkit.com/jsref/regexp.shtml

Reference NO 7

http://www.firedartstudios.com/articles/read/php-tutorial-the-gates-of-regex

Reference NO 8

http://stat.ethz.ch/R-manual/R-devel/library/base/html/regex.html