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copied!<p><code>A[0]</code>, <code>&A</code>, <code>*A</code> all are pointers of distinct types that all point to the same memory location. Same value (sort of), different types. </p> <pre><code>Expression Symmetric Type ---------------------------------------------------------------------------- A address of first row. int[5][5] &A[0][0] address of first element int* &A address of 2d array int(*)[5][5] *A = *( A + 0) = A[0] = address of first element int[5] = decays to int* in a expression </code></pre> <p>My example of 5*4 dimension char arrays: </p> <pre><code> A +---201---202---203---204---206--+ 201 | +-----+-----+-----+-----+-----+| A[0] = *(A + 0)--►| 'f' | 'o' | 'r' | 'g' | 's' || 207 | +-----+-----+-----+-----+-----+| A[1] = *(A + 1)--►| 'd' | 'o' | '\0'| '\0'| '\0'|| 213 | +-----+-----+-----+-----+-----+| A[2] = *(A + 2)--►| 'n' | 'o' | 't' | '\0'| '\0'|| 219 | +-----+-----+-----+-----+-----+| A[3] = *(A + 3)--►| 'd' | 'i' | 'e' | '\0'| '\0'|| | +-----+-----+-----+-----+-----+| +--------------------------------+ </code></pre> <p>A brief explanation about figure example. </p> <blockquote> <ul> <li>In figure <code>A</code> represents complete 2-D array starts with address 201, and</li> <li><code>&A</code> gives address of complete 2-D array = 201</li> <li><code>*A = *(A + 0)</code> = <code>A[0]</code> points to first row = 201 </li> <li>Note value <code>A[0][0]</code> is <code>'f'</code> in my example, and <code>&A[0][0]</code> gives address of <code>[0][0]</code> element = 201 </li> <li>Note <code>&A[0][0]</code> is same as <code>*A</code>, because <code>&A[0][0]</code> => <code>&(*(*A))</code> => <code>&**A</code> => <code>*A</code></li> </ul> </blockquote> <p>So all <code>A[0]</code>, <code>&A</code>, <code>*A</code>, <code>A</code> are same but symmetrically different. </p> <p>To observe difference among the <code>A[0]</code>, <code>&A</code>, <code>*A</code>, <code>A</code>. Type to print <code>sizeof()</code> information. e.g. </p> <pre><code> cout<<sizeof(A[0]) <<" "<<sizeof(&A) <<" "<<sizeof(*A) <<" "<< sizeof(A); </code></pre> <p>Second try to print next location address using: </p> <pre><code> cout<<(A[0] + 1)<<" "<<(&A + 1) <<" "<<(*A + 1)<<" "<<(A + 1); </code></pre> <p><em>For more detailed explanation, must read this <a href="https://stackoverflow.com/a/18364638/2455888">answer</a>.</em></p>

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