Since this doesn't have anything specifically to do with Swing/JFC/AWT GUI stuff, I'm moving this post to the Java In General (Beginner) forum.
(In addition, this sounds suspiciously like a homework problem... and there's a difference between asking "Give me some suggestions/hints/pointers on how to do X" and "Post the code for X so I can cut and paste it into my homework". I'll give a hint... this involves loops and methods on the String class.)
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