### 2.1 Complete Program Example ¶

Here is the complete program that uses the simple, recursive version of the `fib` function (see Example: Recursive Fibonacci):

    #include <stdio.h>

    int
    fib (int n)
    {
      if (n <= 2)  /* This avoids infinite recursion.  */
        return 1;
      else
        return fib (n - 1) + fib (n - 2);
    }

    int
    main (void)
    {
      printf ("Fibonacci series item %d is %d\n",
              20, fib (20));
      return 0;
    }

This program prints a message that shows the value of `fib (20)`.

Now for an explanation of what that code means.