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/*
* Copyright 2002 Adrian Thurston <thurston@complang.org>
*/
/* This file is part of Aapl.
*
* Aapl is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 2.1 of the License, or (at your option)
* any later version.
*
* Aapl is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
* more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Aapl; if not, write to the Free Software Foundation, Inc., 59
* Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _AAPL_INSERTSORT_H
#define _AAPL_INSERTSORT_H
#ifdef AAPL_NAMESPACE
namespace Aapl {
#endif
/**
* \addtogroup sort
* @{
*/
/**
* \class InsertSort
* \brief Insertion sort an array of data.
*
* InsertSort can be used to sort any array of objects of type T provided a
* compare class is given. InsertSort is in-place. It does not require any
* temporary storage.
*
* Objects are not made aware that they are being moved around in memory.
* Assignment operators, constructors and destructors are never invoked by the
* sort.
*
* InsertSort runs in O(n^2) time. It is most useful when sorting small arrays.
* where it can outperform the O(n*log(n)) sorters due to its simplicity.
* InsertSort is a not a stable sort. Elements with the same key will not have
* their relative ordering preserved.
*/
/*@}*/
/* InsertSort. */
template <class T, class Compare> class InsertSort
: public Compare
{
public:
/* Sorting interface routine. */
void sort(T *data, long len);
};
/**
* \brief Insertion sort an array of data.
*/
template <class T, class Compare>
void InsertSort<T,Compare>::sort(T *data, long len)
{
/* For each next largest spot in the sorted array... */
for ( T *dest = data; dest < data+len-1; dest++ ) {
/* Find the next smallest element in the unsorted array. */
T *smallest = dest;
for ( T *src = dest+1; src < data+len; src++ ) {
/* If src is smaller than the current src, then use it. */
if ( compare( *src, *smallest ) < 0 )
smallest = src;
}
if ( smallest != dest ) {
/* Swap dest, smallest. */
char tmp[sizeof(T)];
memcpy( tmp, dest, sizeof(T) );
memcpy( dest, smallest, sizeof(T) );
memcpy( smallest, tmp, sizeof(T) );
}
}
}
#ifdef AAPL_NAMESPACE
}
#endif
#endif /* _AAPL_INSERTSORT_H */
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