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POAre a, &a, *a, a[0], &a[0] and &a[0][0] identical pointers?
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  1. POAre a, &a, *a, a[0], &a[0] and &a[0][0] identical pointers?
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    copied!<p>I have the following C program:</p> <pre><code>#include &lt;stdio.h&gt; int main(){ int a[2][2] = {1, 2, 3, 4}; printf("a:%p, &amp;a:%p, *a:%p \n", a, &amp;a, *a); printf("a[0]:%p, &amp;a[0]:%p \n", a[0], &amp;a[0]); printf("&amp;a[0][0]:%p \n", &amp;a[0][0]); return 0; } </code></pre> <p>It gives the following output:</p> <pre><code>a:0028FEAC, &amp;a:0028FEAC, *a:0028FEAC a[0]:0028FEAC, &amp;a[0]:0028FEAC &amp;a[0][0]:0028FEAC </code></pre> <p>I am not able to understand why are <code>&amp;a</code>, <code>a</code>, <code>*a</code> - all identical. The same for <code>a[0]</code>, <code>&amp;a[0]</code> and <code>&amp;a[0][0]</code>.</p> <p><strong>EDIT:</strong></p> <p>Thanks to the answers, I've understood the reason why these values are coming out to be equal. This line from the book by <em>Kernighan &amp; Ritchie</em> turned out to be the key to my question: </p> <pre><code> the name of an array is a synonym for the location of the initial element. </code></pre> <p>So, by this, we get </p> <p><code>a</code> = <code>&amp;a[0]</code>, and</p> <p><code>a[0]</code> = <code>&amp;a[0][0]</code> (considering <code>a</code> as an array of arrays)</p> <p>Intuitively, now the reason is clear behind the output. But, considering how pointers are implemented in C, I can't understand how <code>a</code> and <code>&amp;a</code> are equal. I am assuming that there is a variable <code>a</code> in memory which points to the array(and the starting address of this array-memory-block would be the value of this variable <code>a</code>). </p> <p>But, when we do <code>&amp;a</code>, doesn't that mean taking the address of the memory location where the variable <code>a</code> was stored? Why are these values equal then?</p>
 

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