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gmp_neg

(PHP 4 >= 4.0.4, PHP 5)

gmp_neg -- Negate number

Description

resource gmp_neg ( resource a )

Returns -a.

例子 1. gmp_neg() example

<?php
$neg1 = gmp_neg("1");
echo gmp_strval($neg1) . "\n";
$neg2 = gmp_neg("-1");
echo gmp_strval($neg2) . "\n";
?>

The printout of the above program will be: 

-1
1
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