source: trunk/doc/src/snippets/code/doc_src_q3memarray.qdoc@ 728

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//! [0]
#include <q3memarray.h>
#include <stdio.h>

Q3MemArray<int> fib( int num ) // returns fibonacci array
{
    Q_ASSERT( num > 2 );
    Q3MemArray<int> f( num ); // array of ints

    f[0] = f[1] = 1;
    for ( int i = 2; i < num; i++ )
        f[i] = f[i-1] + f[i-2];

    return f;
}

int main()
{
    Q3MemArray<int> a = fib( 6 ); // get first 6 fibonaccis
    for ( int i = 0; i < a.size(); i++ )
        qDebug( "%d: %d", i, a[i] );

    qDebug( "1 is found %d times", a.contains(1) );
    qDebug( "5 is found at index %d", a.find(5) );

    return 0;
}
//! [0]


//! [1]
0: 1
1: 1
2: 2
3: 3
4: 5
5: 8
1 is found 2 times
5 is found at index 4
//! [1]


//! [2]
// MyStruct may be padded to 4 or 8 bytes
struct MyStruct
{
    short i; // 2 bytes
    char c;  // 1 byte
};

Q3MemArray<MyStruct> a(1);
a[0].i = 5;
a[0].c = 't';

MyStruct x;
x.i = '5';
x.c = 't';
int i = a.find( x ); // may return -1 if the pad bytes differ
//! [2]


//! [3]
static char bindata[] = { 231, 1, 44, ... };
QByteArray      a;
a.setRawData( bindata, sizeof(bindata) );       // a points to bindata
QDataStream s( a, IO_ReadOnly );                // open on a's data
s >> <something>;                               // read raw bindata
a.resetRawData( bindata, sizeof(bindata) ); // finished
//! [3]


//! [4]
static char bindata[] = { 231, 1, 44, ... };
QByteArray      a, b;
a.setRawData( bindata, sizeof(bindata) );       // a points to bindata
a.resize( 8 );                          // will crash
b = a;                                  // will crash
a[2] = 123;                                     // might crash
// forget to resetRawData: will crash
//! [4]