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| 22 | <title>Example of for (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="Loop-Statements.html" rel="up" title="Loop Statements">
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| 33 | <link href="Omitted-for_002dExpressions.html" rel="next" title="Omitted for-Expressions">
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| 57 | <body lang="en">
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| 58 | <span id="Example-of-for"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Omitted-for_002dExpressions.html" accesskey="n" rel="next">Omitted for-Expressions</a>, Previous: <a href="for-Statement.html" accesskey="p" rel="prev">for Statement</a>, Up: <a href="Loop-Statements.html" accesskey="u" rel="up">Loop Statements</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="Example-of-for-1"></span><h4 class="subsection">19.6.5 Example of <code>for</code></h4>
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| 64 |
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| 65 | <p>Here is the <code>for</code> statement from the iterative Fibonacci
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| 66 | function:
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| 67 | </p>
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| 68 | <div class="example">
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| 69 | <pre class="example">int i;
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| 70 | for (i = 1; i < n; ++i)
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| 71 | /* <span class="roman">If <code>n</code> is 1 or less, the loop runs zero times,</span> */
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| 72 | /* <span class="roman">since <code>i < n</code> is false the first time.</span> */
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| 73 | {
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| 74 | /* <span class="roman">Now <var>last</var> is <code>fib (<var>i</var>)</code></span>
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| 75 | <span class="roman">and <var>prev</var> is <code>fib (<var>i</var> - 1)</code>.</span> */
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| 76 | /* <span class="roman">Compute <code>fib (<var>i</var> + 1)</code>.</span> */
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| 77 | int next = prev + last;
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| 78 | /* <span class="roman">Shift the values down.</span> */
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| 79 | prev = last;
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| 80 | last = next;
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| 81 | /* <span class="roman">Now <var>last</var> is <code>fib (<var>i</var> + 1)</code></span>
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| 82 | <span class="roman">and <var>prev</var> is <code>fib (<var>i</var>)</code>.</span>
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| 83 | <span class="roman">But that won’t stay true for long,</span>
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| 84 | <span class="roman">because we are about to increment <var>i</var>.</span> */
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| 85 | }
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| 86 | </pre></div>
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| 87 |
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| 88 | <p>In this example, <var>start</var> is <code>i = 1</code>, meaning set <code>i</code> to
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| 89 | 1. <var>continue-test</var> is <code>i < n</code>, meaning keep repeating the
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| 90 | loop as long as <code>i</code> is less than <code>n</code>. <var>advance</var> is
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| 91 | <code>i++</code>, meaning increment <code>i</code> by 1. The body is a block
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| 92 | that contains a declaration and two statements.
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| 93 | </p>
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| 94 |
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| 95 |
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| 96 |
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| 97 | </body>
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| 98 | </html>
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