title: Regular Expression Dictionary Search Single Use Letters
body: <p>I'm working on a Java program that searches through a dictionary for words made up of a particular set of letters. I am wondering if it's possible to set up a regular expression that would let you use a character only as often as it appears in a string. For example, with the letters SHARE. Hear, hares, sea, are etc. would be valid. But see or sarah would not be valid because you only have one e or one a respectively.</p>