title: Write regular expression for C numerical literals
body: <p>My homework is to write a regular expression representing the language of numerical literals from C programming language. I can use l for letter, d for digit, a for +, m for -, and p for point. Assume that there are no limits on the number of consecutive digits in any part of the expression.</p>
  
  <p>Some of the examples of valid numerical literals were 13. , .328, 41.16, +45.80, -2.e+7, -.4E-7, 01E-06, +0</p>
  
  <p>I came up with: (d+p+a+m)(d+p+E+e+a+m)*<br>
  update2: (l+d+p+a+m)(d+p+((E+e)(a+m+d)d*) )* im not sure how to prevent something like 1.0.0.0eee-e1.</p>