C Program to Sort an array of names or strings

Given an array of strings in which all characters are of the same case, write a C function to sort them alphabetically.  The idea is to use qsort() in C and write a comparison function that uses strcmp() to compare two strings. 

Given array is
0: geeksforgeeks 
1: geeksquiz 
2: clanguage 

Sorted array is
0: clanguage 
1: geeksforgeeks 
2: geeksquiz 

Time Complexity: O(nlogn)
Auxiliary Space: O(1)