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copied!<p>The first makes a variable named <code>arr</code> that is of an array length 5 of type <code>int*</code>, so it is an array length 5 of int pointers. </p> <p>The second declares a variable named <code>arr</code> that is a pointer to an array length 5 of type int. So it is a pointer to an array of ints length 5.</p> <p>The third is a variable named arr that is a pointer to an array of length 5 of type int pointer. So it is a pointer to an array length 5 of int pointers. Or, a pointer to the type of the first case! </p> <p>To think of how to analyze things like this in the future, realize that parenthesis have the highest priority here so by having <code>(*arr)</code> it is first, and foremost, a pointer. Then the array notation has second highest priority, so <code>(*arr)[5]</code> is a pointer to an array of length 5...but what type of array? Well the type is the lowest priority, so that comes last. If we have int <code>(*arr)[5]</code>, then it is a pointer (1st) to an array length 5 (2) of type int (3). </p> <p>With that we can look at something like: <code>int** (*arr)[7]</code> It is a pointer named <code>arr</code> (1) to an array length 7 (2) of type <code>int**</code>, or pointers to pointers of ints (3). </p> <p>As far as wondering how pointers/arrays are represented in C...</p> <p>pointers and arrays are both 32 bit variables (like ints on most systems) that contain a 32 bit address to a memory location (where they point). Arrays obviously point to the beginning of an array, so <code>*arr == arr[0]</code>. While pointers can point to anything. When you declare an array (<code>arr[5]</code>, <code>arr[1000]</code>, etc.) it makes a pointer named <code>arr</code> as well as reserves whatever space is in between the brackets (5 or 1000). But when you declare a pointer <code>(*arr)</code>, it does not reserve any space. Otherwise, the variable arr in both cases is simply a pointer. Also, if you want to be confusing, you could even dereference your pointers like so: <code>pointer[0]</code>, instead of <code>*pointer</code>. </p> <p>As a final note example, we can look at something like: <code>int * (*arr)[5][7]</code> and analyze both what it is and what the compiler is doing:</p> <p>First, it is a pointer named <code>arr</code> (1), to an array length 5 (2) each to an array length 7 (3) but because an array length n is just a pointer to a reserved location in memory, so really (2) is an array length 5 to a pointer (pointing to memory blocks of size 7). Finally, each of the memory blocks of size 7 (3) is of type <code>int *</code> (4). </p> <p>So, it is a pointer to an array length 5 of pointers to arrays of length 7 of type <code>int *</code>!</p> <p>I hope this helps! I know I had a lot of fun playing with C and seeing what was possible and what different things did =)</p>

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