Appendix CWriting Your Own Functions. . . . . . . . . . . . . . . . . . 487
The Structure of Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 488
Returning Values from Functions. . . . . . . . . . . . . . . . . . . . . . . 488
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