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C++, array of pointers to objects

Posted on 2013-01-22
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Last Modified: 2013-01-22
Hello experts, please have a look at the code below:

#include <iostream>
using namespace std;

class Dog{
public:
	int x;

};

int main(){
	Dog * matrix[12];
	int * matrixInt[12];

	*matrixInt[0] = 12; //works fine
	*matrix[0]->x = 12; //does not work

	return 0;
}

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How can I make it work?
Thank you

panJames
0
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Question by:panJames
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1 Comment
 
LVL 31

Accepted Solution

by:
Zoppo earned 500 total points
ID: 38804963
Hi panJames,

you're declaring array to pointers, but the pointers are uninitialized. You need to allocate memory for them, i.e.:
Dog* matrix[12];
for ( int i = 0; i < 12; i++ )
{
 matrix[i] = new Dog;
}
...
// need to clean up when you don't need it anymore.
for ( int i = 0; i < 12; i++ )
{
 delete matrix[i];
}

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(do it similar for the matrixInt)

Hope this helps,

ZOPPO
0

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