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| 22 | <title>Basic Arithmetic (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="Arithmetic.html" rel="up" title="Arithmetic">
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| 33 | <link href="Integer-Arithmetic.html" rel="next" title="Integer Arithmetic">
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| 57 | <body lang="en">
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| 58 | <span id="Basic-Arithmetic"></span><div class="header">
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| 59 | <p>
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| 60 | Next: <a href="Integer-Arithmetic.html" accesskey="n" rel="next">Integer Arithmetic</a>, Up: <a href="Arithmetic.html" accesskey="u" rel="up">Arithmetic</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="Basic-Arithmetic-1"></span><h3 class="section">6.1 Basic Arithmetic</h3>
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| 64 | <span id="index-addition-operator"></span>
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| 65 | <span id="index-subtraction-operator"></span>
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| 66 | <span id="index-multiplication-operator"></span>
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| 67 | <span id="index-division-operator"></span>
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| 68 | <span id="index-negation-operator"></span>
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| 69 | <span id="index-operator_002c-addition"></span>
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| 70 | <span id="index-operator_002c-subtraction"></span>
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| 71 | <span id="index-operator_002c-multiplication"></span>
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| 72 | <span id="index-operator_002c-division"></span>
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| 73 | <span id="index-operator_002c-negation"></span>
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| 74 |
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| 75 | <p>Basic arithmetic in C is done with the usual binary operators of
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| 76 | algebra: addition (‘<samp>+</samp>’), subtraction (‘<samp>-</samp>’), multiplication
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| 77 | (‘<samp>*</samp>’) and division (‘<samp>/</samp>’). The unary operator ‘<samp>-</samp>’ is
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| 78 | used to change the sign of a number. The unary <code>+</code> operator also
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| 79 | exists; it yields its operand unaltered.
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| 80 | </p>
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| 81 | <p>‘<samp>/</samp>’ is the division operator, but dividing integers may not give
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| 82 | the result you expect. Its value is an integer, which is not equal to
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| 83 | the mathematical quotient when that is a fraction. Use ‘<samp>%</samp>’ to
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| 84 | get the corresponding integer remainder when necessary.
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| 85 | See <a href="Division-and-Remainder.html">Division and Remainder</a>. Floating point division yields value
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| 86 | as close as possible to the mathematical quotient.
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| 87 | </p>
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| 88 | <p>These operators use algebraic syntax with the usual algebraic
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| 89 | precedence rule (see <a href="Binary-Operator-Grammar.html">Binary Operator Grammar</a>) that multiplication
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| 90 | and division are done before addition and subtraction, but you can use
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| 91 | parentheses to explicitly specify how the operators nest. They are
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| 92 | left-associative (see <a href="Associativity-and-Ordering.html">Associativity and Ordering</a>). Thus,
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| 93 | </p>
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| 94 | <div class="example">
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| 95 | <pre class="example">-a + b - c + d * e / f
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| 96 | </pre></div>
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| 97 |
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| 98 | <p>is equivalent to
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| 99 | </p>
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| 100 | <div class="example">
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| 101 | <pre class="example">(((-a) + b) - c) + ((d * e) / f)
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| 102 | </pre></div>
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| 103 |
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| 104 |
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| 105 |
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| 106 |
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