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    <p>A <code>char[5][5]</code> <strong>is not</strong> a <code>char **</code>.</p> <p>Declare your <code>path</code> function as one of these (they are equivalent):</p> <pre><code>void path(char (*adj_mat)[5], int u, int v) void path(char adj_mat[5][5], int u, int v) </code></pre> <p>and use it like</p> <pre><code>path(mat, u, v); </code></pre> <hr> <p>Update: Now to the reason for the segfault.</p> <p><code>mat</code> is a 5-array of 5-arrays of <code>char</code>, which will "decay" into a pointer to 5-arrays of <code>char</code> when used as an expression. This means that <code>mat</code> can be used as if it is a pointer to a 5-array. In general a n-array of type <code>T</code> will decay into a pointer of type <code>T</code> (note that <code>T</code> does <strong>not</strong> decay!).</p> <p>So note you use <code>mat</code> as an expression when you pass it to your function <code>pass()</code>. In C it is not possible to pass an array as-is to a function, but it can only "receive" pointers.</p> <p>So what's the difference between a pointer to pointer of <code>char</code> and a pointer to a 5-array of <code>char</code>? Their type. And their sizes.</p> <p>Suppose you have a pointer to a pointer to a <code>char</code> - let's call it <code>p</code> and we have a pointer to a 5-array <code>q</code>. In short: <code>char **p</code> and <code>char (*q)[5]</code>.</p> <p>When you write <code>p[i]</code>, this will be equivalent to <code>*(p+i)</code>. Here you have pointer arithmetic. <code>p+i</code> has the value (which is an adress) <code>p</code> plus <code>i*sizeof(char *)</code> because <code>p</code> points to a <code>char *</code>.</p> <p>When you look at <code>q</code>, <code>q+i</code> would have the value <code>q</code> plus <code>i*sizeof(char[5])</code>.</p> <p>These will almost always be different!</p> <hr> <p><strong>Update</strong> (real answer now): It's even worse in your case as you are "forcing" <code>char (*q)[5]</code> "to be" a <code>char p**</code> (via your invalid typecast), so in your call</p> <pre><code>char temp = *adj_mat[1]; </code></pre> <p><code>adj_mat[1]</code> will look at the 2nd row of your matrix an try to interpret its value as a pointer (but it is a 5-array!), so when you then dereference via <code>*adj_mat[1]</code> you will land somewhere in nirvana - segfault!</p>
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    1. POSegmentation fault when running C program (putchar() and multidimensional array pointers)
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    1. CONow i'm getting: **ex1_1.c: In function ‘main’: ex1_1.c:26: warning: passing argument 1 of ‘path’ from incompatible pointer type**
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    2. COHow did you declare `path` and how are you calling it? If you did like I told, you should have no problems.
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    3. CO@user128877: So.. did you get it running?
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