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| 22 | <title>switch Example (GNU C Language Manual)</title>
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| 30 | <link href="Symbol-Index.html" rel="index" title="Symbol Index">
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| 31 | <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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| 32 | <link href="Statements.html" rel="up" title="Statements">
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| 33 | <link href="Duffs-Device.html" rel="next" title="Duffs Device">
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| 34 | <link href="switch-Statement.html" rel="prev" title="switch Statement">
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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="switch-Example"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Duffs-Device.html" accesskey="n" rel="next">Duffs Device</a>, Previous: <a href="switch-Statement.html" accesskey="p" rel="prev">switch Statement</a>, Up: <a href="Statements.html" accesskey="u" rel="up">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-switch"></span><h3 class="section">19.8 Example of <code>switch</code></h3>
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| 64 |
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| 65 | <p>Here’s an example of using the <code>switch</code> statement
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| 66 | to distinguish among characters:
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| 67 | </p>
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| 68 | <span id="index-counting-vowels-and-punctuation"></span>
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| 69 | <div class="example">
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| 70 | <pre class="example">struct vp { int vowels, punct; };
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| 71 |
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| 72 | struct vp
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| 73 | count_vowels_and_punct (char *string)
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| 74 | {
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| 75 | int c;
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| 76 | int vowels = 0;
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| 77 | int punct = 0;
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| 78 | /* <span class="roman">Don’t change the parameter itself.</span> */
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| 79 | /* <span class="roman">That helps in debugging.</span> */
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| 80 | char *p = string;
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| 81 | struct vp value;
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| 82 |
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| 83 | while (c = *p++)
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| 84 | switch (c)
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| 85 | {
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| 86 | case 'y':
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| 87 | case 'Y':
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| 88 | /* <span class="roman">We assume <code>y_is_consonant</code> will check surrounding
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| 89 | letters to determine whether this y is a vowel.</span> */
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| 90 | if (y_is_consonant (p - 1))
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| 91 | break;
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| 92 |
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| 93 | /* <span class="roman">Falls through</span> */
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| 94 |
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| 95 | case 'a':
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| 96 | case 'e':
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| 97 | case 'i':
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| 98 | case 'o':
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| 99 | case 'u':
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| 100 | case 'A':
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| 101 | case 'E':
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| 102 | case 'I':
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| 103 | case 'O':
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| 104 | case 'U':
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| 105 | vowels++;
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| 106 | break;
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| 107 |
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| 108 | case '.':
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| 109 | case ',':
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| 110 | case ':':
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| 111 | case ';':
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| 112 | case '?':
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| 113 | case '!':
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| 114 | case '\"':
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| 115 | case '\'':
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| 116 | punct++;
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| 117 | break;
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| 118 | }
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| 119 |
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| 120 | value.vowels = vowels;
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| 121 | value.punct = punct;
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| 122 |
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| 123 | return value;
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| 124 | }
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| 125 | </pre></div>
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| 126 |
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| 127 |
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| 128 |
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| 129 |
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| 130 | </body>
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| 131 | </html>
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