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POdynamic array of structs in C
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copied!<p>I am trying to learn about structs, pointers, and dynamic arrays in C. I don't understand how to create a dynamic array of structs using pointers. My code doesn't work, and I don't know what's wrong with it. I have seen several examples of dynamic arrays, but non with structs. Any help would be appreciated. Please give some explanation, not just code snippets as I do want to understand not just solve this problem. </p> <pre><code>#include<stdio.h> #include<stdlib.h> #include <string.h> struct *struct_array; int i,m,n,p; struct data { char inputA[20]; char inputB[20]; }; struct data get_data() { struct data thisdata; printf("Please enter input A\n"); scanf("%s", thisdata.inputA); printf("Please enter input B\n"); scanf("%s", thisdata.inputB); return thisdata; } void Output(struct data struct_array, int n) { int index = 0; for(i = 0; i<n ;i++) { printf("%s ", struct_array[i].inputA); printf("%s ", struct_array[i].inputB); } } void resizeArray(int n) { struct_array = (int*)realloc(n*sizeof(int)); } void mainMenu() { 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", &p); if(p == 1) { printf("Please enter the number of students to register:\n"); scanf("%d", &n); resizeArray(n); for(i = n; i<n ;i++) { struct_array[i] = get_data(); } } else if(p == 2) { Output(struct_array, n); } else { free(struct_array); exit(0); } } int main() { struct_array = (int*)realloc(2*sizeof(int)); mainMenu(); } </code></pre>

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