cin, cout, matrix, pointers and references :(

[Deepak]

i am working with a matrix manipulation program…consists of a matrix class and its member functions..i have also overloaded << and >>…so dat dey can read and print d whole matrix at one statement..the code of these overloaded operators is something like this..

<br /> // for >> (cin) :<br /> istream&#038; operator >> (istream &#038;read, matrix &#038;mat)<br /> {<br /> for (int i = 0; i < mat.rows * mat.columns; ++i)<br /> read >> *(mat.element+i);<br /> return read;<br /> }<br /> <br /> // for << (cout) :<br /> ostream&#038; operator << (ostream &#038;print, matrix &#038;mat)<br /> {<br /> for (int i = 0; i < mat.rows; ++i)<br /> {<br /> for (int j = 0; j < mat.columns; ++j)<br /> {<br /> print << *mat.element << " ";<br /> ++mat.element;<br /> }<br /> print << endl;<br /> }<br /> mat.element -= mat.rows * mat.columns;<br /> return print;<br /> }

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<br /> // for >> (cin) :<br /> istream&#038; operator >> (istream &#038;read, matrix &#038;mat)<br /> {<br /> for (int i = 0; i < mat.rows * mat.columns; ++i)<br /> read >> *(mat.element+i);<br /> return read;<br /> }<br /> <br /> // for << (cout) :<br /> ostream&#038; operator << (ostream &#038;print, matrix &#038;mat)<br /> {<br /> for (int i = 0; i < mat.rows; ++i)<br /> {<br /> for (int j = 0; j < mat.columns; ++j)<br /> {<br /> print << *mat.element << "  ";<br /> ++mat.element;<br /> }<br /> print << endl;<br /> }<br /> mat.element -= mat.rows * mat.columns;<br /> return print;<br /> }

here i have received the variable matrix1 by reference…in main() i have used a variable matrix1 which is passed as follows :matrix matrix1;cin >> matrix1;now…my question is : wat if i want to pass a pointer variable which should be received by a reference…smthing like this…

<br /> main()<br /> {<br /> matrix *matrix2;<br /> cin >> matrix2; //i aint sure that this statement is right...it may be cin >> *matrix2...<br /> }<br />

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<br /> main()<br /> {<br /> matrix *matrix2;<br /> cin >> matrix2; //i aint sure that this statement is right...it may be cin >> *matrix2...<br /> }<br />

the overloaded function for pointer thing is coded as follows :

for >> :<br /> istream&#038; operator >> (istream &#038;read, matrix *&#038;mat)<br /> {<br /> for (int i = 0; i < mat->rows * mat->columns; ++i)<br /> read >> *(mat->element+i);<br /> return read;<br /> }<br /> <br /> // for << :<br /> ostream&#038; operator << (ostream &#038;print, matrix *&#038;mat)<br /> {<br /> <br /> for (int i = 0; i < mat->rows; ++i)<br /> {<br /> for (int j = 0; j < mat->columns; ++j)<br /> {<br /> print << *mat->element << " ";<br /> ++mat->element;<br /> }<br /> print << endl;<br /> }<br /> mat->element -= mat->rows * mat->columns;<br /> return print;<br /> }<br />

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for >> :<br /> istream&#038; operator >> (istream &#038;read, matrix *&#038;mat)<br /> {<br /> for (int i = 0; i < mat->rows * mat->columns; ++i)<br /> read >> *(mat->element+i);<br /> return read;<br /> }<br /> <br /> // for << :<br /> ostream&#038; operator << (ostream &#038;print, matrix *&#038;mat)<br /> {<br /> <br /> for (int i = 0; i < mat->rows; ++i)<br /> {<br /> for (int j = 0; j < mat->columns; ++j)<br /> {<br /> print << *mat->element << "  ";<br /> ++mat->element;<br /> }<br /> print << endl;<br /> }<br /> mat->element -= mat->rows * mat->columns;<br /> return print;<br /> }<br />

however my problem is when i execute the program…then while taking input for a pointer matrix…it just reads one value instead of all the values..but doesnt even print that single value..i think there must be bug in those overloaded functions used for pointer variable.. :(so please check out the functions and post the solution or your suggestions…

[Humayan]

Can you post the whole code?

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