question2.c

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define SIZE 50

void sort(const char* arr[], int n);
void myFgets(char str[], int n);
int myCompare(const void* a, const void* b);

int main()
{
    int friendsNumber = 0, i = 0;
    char str[SIZE] = { 0 };
    char** names;

    printf("Enter number of friends: ");
    scanf("%d", &friendsNumber);
    getchar();

    names = (char**)malloc(sizeof(char*) * friendsNumber); //allocating size to the pointer (to another arrays..)

    for (i = 0; i < friendsNumber; i++)
    {
        printf("Enter name of friend %d: ", i + 1);
        myFgets(str, SIZE);

        names[i] = (char*)malloc(sizeof(char) * strlen(str) + 1); //allocating size to EACH pointer (array) (by the name (str) length)

        strcpy(names[i], str);
    }
    sort(names, friendsNumber);
    for (i = 0; i < friendsNumber; i++)
    {
        printf("Friend %d: %s\n", i + 1, names[i]);
        free(names[i]);
    }

    free(names);

    getchar();
    return 0;
}
/*
* Full fgets() function
* input: string to input, string length
* output: -
*/
void myFgets(char str[], int n)
{
    fgets(str, n, stdin);
    str[strcspn(str, "\n")] = 0;
}
/*
* Defining comparator function as per the requirement
* input: two constans to compare
* output:

    Return value < 0 then it indicates a is less than b.

    Return value > 0 then it indicates b is less than a.

    Return value = 0 then it indicates a is equal to b.

*/
int myCompare(const void* a, const void* b)
{
    return strcmp(*(const char**)a, *(const char**)b);
}
/*
* Function to sort the array
* input: array to sort, array size (length)
* output: -
*/
void sort(const char* arr[], int n)
{
    // calling qsort function to sort the array
    // with the help of Comparator
    qsort(arr, n, sizeof(char*), myCompare);
}