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    <p>I believe that the problem with your <code>operator &gt;&gt;</code> is that you're using whatever dimensions already happen to be in the <code>Matrix</code> rather than trying to recover the dimensions from the input that you find.</p> <p>I think that your best bet would be to have the <code>operator &lt;&lt;</code> implementation preface the matrix with dimension information (such as the number of rows and columns) and then have the <code>operator &gt;&gt;</code> function read in that information. For example:</p> <pre><code>ostream &amp;operator&lt;&lt;(ostream &amp;out, const Matrix &amp;m) { out &lt;&lt; m.dx &lt;&lt; ' ' &lt;&lt; out.dy &lt;&lt; '\n'; for (int i = 0; i &lt; m.dx; ++i) { for (int j = 0; j &lt; m.dy; ++j) out &lt;&lt; m.p[i][j] &lt;&lt; " "; out &lt;&lt; endl; } return out; } </code></pre> <p>With this in hand, you can write your stream extraction operator as</p> <pre><code>istream &amp;operator&gt;&gt;(istream &amp;in, Matrix &amp;m) { in &gt;&gt; m.dx &gt;&gt; m.dy; /* Some sort of logic to ensure that you've allocated an array large enough to * hold all the elements ... */ for (int i = 0; i &lt; m.dx; ++i) { for (int j = 0; j &lt; m.dy; ++j) in &gt;&gt; m.p[i][j]; } return in; } </code></pre> <p>This may not be the most aesthetically pleasing input and output operators, but they should get the job done.</p> <p>If you want to make these operators a bit classier, consider outputting the elements of the matrix using some special character to delimit rows and columns. For example, you might try outputting the matrix</p> <pre><code>0 1 2 3 4 5 6 7 8 </code></pre> <p>as</p> <pre><code>[[0 1 2][3 4 5][6 7 8]] </code></pre> <p>With this setup, the size information about the matrix is implicit in how the bracket grouping works. Then again, this may make it a bit trickier to read the input, since you wouldn't know in advance how large the matrix is. But go with what's easiest for yourself overall.</p> <p>As an FYI, you probably don't want to use <code>endl</code> to delimit lines when writing a stream insertion operator. In addition to writing a newline, <code>endl</code> flushes the buffer. If your stream is hooked up to a network connection, you may not want to keep flushing the buffer whenever you have a new line of the matrix, since that could result in a lot of data getting sent in bursts (slow) rather than grouping it all together at once (fast).</p> <p>Hope this helps!</p>
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    1. POTrouble overloading operator >> for a matrix class
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    1. COthere is option to overload cin operator and inside the operator get string of numbers like `1 98 3 5 3` and insert each number to array that the cin operator get?
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