50 lines
754 B
C
50 lines
754 B
C
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/*
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FUNCTION
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<<labs>>---long integer absolute value
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INDEX
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labs
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ANSI_SYNOPSIS
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#include <stdlib.h>
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long labs(long <[i]>);
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TRAD_SYNOPSIS
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#include <stdlib.h>
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long labs(<[i]>)
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long <[i]>;
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DESCRIPTION
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<<labs>> returns
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@tex
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$|x|$,
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@end tex
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the absolute value of <[i]> (also called the magnitude
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of <[i]>). That is, if <[i]> is negative, the result is the opposite
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of <[i]>, but if <[i]> is nonnegative the result is <[i]>.
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The similar function <<abs>> uses and returns <<int>> rather than
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<<long>> values.
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RETURNS
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The result is a nonnegative long integer.
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PORTABILITY
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<<labs>> is ANSI.
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No supporting OS subroutine calls are required.
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*/
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#include <stdlib.h>
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long
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_DEFUN (labs, (x),
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long x)
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{
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if (x < 0)
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{
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x = -x;
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}
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return x;
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}
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