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| 22 | <title>Complete Line-by-Line (GNU C Language Manual)</title>
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| 31 | <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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| 32 | <link href="Complete-Program.html" rel="up" title="Complete Program">
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| 33 | <link href="Compile-Example.html" rel="next" title="Compile Example">
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| 55 | </head>
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| 56 |
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| 57 | <body lang="en">
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| 58 | <span id="Complete-Line_002dby_002dLine"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Compile-Example.html" accesskey="n" rel="next">Compile Example</a>, Previous: <a href="Complete-Explanation.html" accesskey="p" rel="prev">Complete Explanation</a>, Up: <a href="Complete-Program.html" accesskey="u" rel="up">Complete Program</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Index.html" title="Index" rel="index">Index</a>]</p>
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| 61 | </div>
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| 62 | <hr>
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| 63 | <span id="Complete-Program_002c-Line-by-Line"></span><h3 class="section">2.3 Complete Program, Line by Line</h3>
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| 64 |
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| 65 | <p>Here’s the same example, explained line by line.
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| 66 | <strong>Beginners, do you find this helpful or not?
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| 67 | Would you prefer a different layout for the example?
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| 68 | Please tell rms@gnu.org.</strong>
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| 69 | </p>
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| 70 | <div class="example">
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| 71 | <pre class="example">#include <stdio.h> /* <span class="roman">Include declaration of usual</span> */
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| 72 | /* <span class="roman">I/O functions such as <code>printf</code>.</span> */
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| 73 | /* <span class="roman">Most programs need these.</span> */
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| 74 |
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| 75 | int /* <span class="roman">This function returns an <code>int</code>.</span> */
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| 76 | fib (int n) /* <span class="roman">Its name is <code>fib</code>;</span> */
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| 77 | /* <span class="roman">its argument is called <code>n</code>.</span> */
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| 78 | { /* <span class="roman">Start of function body.</span> */
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| 79 | /* <span class="roman">This stops the recursion from being infinite.</span> */
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| 80 | if (n <= 2) /* <span class="roman">If <code>n</code> is 1 or 2,</span> */
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| 81 | return 1; /* <span class="roman">make <code>fib</code> return 1.</span> */
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| 82 | else /* <span class="roman">otherwise, add the two previous</span> */
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| 83 | /* <span class="roman">fibonacci numbers.</span> */
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| 84 | return fib (n - 1) + fib (n - 2);
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| 85 | }
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| 86 |
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| 87 | int /* <span class="roman">This function returns an <code>int</code>.</span> */
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| 88 | main (void) /* <span class="roman">Start here; ignore arguments.</span> */
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| 89 | { /* <span class="roman">Print message with numbers in it.</span> */
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| 90 | printf ("Fibonacci series item %d is %d\n",
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| 91 | 20, fib (20));
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| 92 | return 0; /* <span class="roman">Terminate program, report success.</span> */
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| 93 | }
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| 94 | </pre></div>
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| 95 |
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| 96 |
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| 97 |
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| 98 |
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| 99 | </body>
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| 100 | </html>
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