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    <p>You have several errors in your source code:</p> <ul> <li><p><code>struct *struct_array;</code> (l. 5)<br> What does it mean? Did you want to write <code>struct data *struct_array</code>? </p></li> <li><p><code>printf("%s ", struct_array[i].inputA);</code> (l.32 &amp; l. 33)<br> The argument <code>struct_array</code> masks the global declaration, and it is not an array. Why did you add this argument?</p></li> <li><p><code>struct_array = (int *)realloc(n * sizeof(int));</code> (l. 39)<br> You have forgotten an argument. Did you want to use <code>malloc</code> instead? Besides, the cast is not necessary (and incorrect!).</p></li> <li><p>Unless you are using an hosted environnment and C99/C11, you should return a value from <code>main</code>.</p></li> <li><p>Your variable <code>index</code> is not used. Why did you declare it?</p></li> <li><p><code>for(i = n; i &lt; n; i++)</code> (l. 53) You won't have any iteration here...</p></li> </ul> <p>The following code works as expected.</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;string.h&gt; /* TODO: Avoid global variables. */ struct data *struct_array; struct data { char inputA[20]; char inputB[20]; }; /* * TODO: Try to avoid passing your structure (40 bytes + padding) * without pointer. */ struct data get_data(void) { struct data thisdata; printf("Please enter input A\n"); /* TODO: Avoid using `scanf` for human inputs. */ scanf("%s", thisdata.inputA); printf("Please enter input B\n"); scanf("%s", thisdata.inputB); return thisdata; } void Output(size_t n) { size_t i; for (i = 0; i &lt; n; i++) { printf("%s ", struct_array[i].inputA); printf("%s ", struct_array[i].inputB); } } void resizeArray(size_t n) { /* TODO: Handle reallocations errors. */ struct_array = realloc(struct_array, n * sizeof *struct_array); } void mainMenu(void) { size_t i, n; int p; /* TODO: Use a loop ? */ printf("Please select from the following options:\n"); printf("1: Add new students to database\n"); printf("2: Display current student database contents\n"); printf("3: exit the program\n"); scanf("%d", &amp;p); switch (p) { case 1: printf("Please enter the number of students to register:\n"); scanf("%u", &amp;n); resizeArray(n); for (i = 0; i &lt; n; i++) struct_array[i] = get_data(); break; case 2: Output(n); break; } } int main(void) { struct_array = malloc(2 * sizeof(int)); mainMenu(); free(struct_array); return 0; } </code></pre>
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    1. POdynamic array of structs in C
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    1. COI don't really understand how allocating memory to a pointer is used as/for an array. I tried creating an array and using the pointer as the length (array[pointer]) but didn't work. I really don't get it and I've read several examples that just don'e seem to help me grasp the whole concept.
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    2. COI give an example in my EDIT.
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    3. COYou can only do one operation i the `mainMenu()`; it really needs a loop somewhere — around its call or in its body.
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      1. USJonathan Leffler
 

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