doc/src/snippets/code/doc_src_q3memarray.qdoc
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/****************************************************************************
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**
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** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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** All rights reserved.
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** Contact: Nokia Corporation (qt-info@nokia.com)
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:LGPL$
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** No Commercial Usage
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** This file contains pre-release code and may not be distributed.
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** You may use this file in accordance with the terms and conditions
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** contained in the Technology Preview License Agreement accompanying
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** this package.
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**
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** GNU Lesser General Public License Usage
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** Alternatively, this file may be used under the terms of the GNU Lesser
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** General Public License version 2.1 as published by the Free Software
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** Foundation and appearing in the file LICENSE.LGPL included in the
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** packaging of this file.  Please review the following information to
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** ensure the GNU Lesser General Public License version 2.1 requirements
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** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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**
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** In addition, as a special exception, Nokia gives you certain additional
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** rights.  These rights are described in the Nokia Qt LGPL Exception
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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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**
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** If you have questions regarding the use of this file, please contact
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** Nokia at qt-info@nokia.com.
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**
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**
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**
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**
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**
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**
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**
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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//! [0]
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#include <q3memarray.h>
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#include <stdio.h>
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Q3MemArray<int> fib( int num ) // returns fibonacci array
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{
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    Q_ASSERT( num > 2 );
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    Q3MemArray<int> f( num ); // array of ints
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    f[0] = f[1] = 1;
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    for ( int i = 2; i < num; i++ )
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	f[i] = f[i-1] + f[i-2];
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    return f;
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}
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int main()
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{
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    Q3MemArray<int> a = fib( 6 ); // get first 6 fibonaccis
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    for ( int i = 0; i < a.size(); i++ )
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	qDebug( "%d: %d", i, a[i] );
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    qDebug( "1 is found %d times", a.contains(1) );
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    qDebug( "5 is found at index %d", a.find(5) );
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    return 0;
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}
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//! [0]
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//! [1]
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0: 1
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1: 1
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2: 2
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3: 3
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4: 5
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5: 8
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1 is found 2 times
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5 is found at index 4
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//! [1]
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//! [2]
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// MyStruct may be padded to 4 or 8 bytes
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struct MyStruct
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{
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    short i; // 2 bytes
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    char c;  // 1 byte
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};
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Q3MemArray<MyStruct> a(1);
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a[0].i = 5;
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a[0].c = 't';
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MyStruct x;
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x.i = '5';
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x.c = 't';
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int i = a.find( x ); // may return -1 if the pad bytes differ
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//! [2]
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//! [3]
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static char bindata[] = { 231, 1, 44, ... };
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QByteArray	a;
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a.setRawData( bindata, sizeof(bindata) );	// a points to bindata
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QDataStream s( a, IO_ReadOnly );		// open on a's data
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s >> <something>;				// read raw bindata
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a.resetRawData( bindata, sizeof(bindata) ); // finished
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//! [3]
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//! [4]
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static char bindata[] = { 231, 1, 44, ... };
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QByteArray	a, b;
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a.setRawData( bindata, sizeof(bindata) );	// a points to bindata
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a.resize( 8 );				// will crash
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b = a;					// will crash
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a[2] = 123;					// might crash
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// forget to resetRawData: will crash
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//! [4]