Write the following functions in C.

char *concat_strings (char *, char *); Convert both strings passed in as arguments into two lists, join the lists into one, and copy the elements of the new big list into a new string. Free the lists used and return a pointer the newly allocated string. This function takes two pointers to characters (strings), concatenates them, and returns a pointer to the new string. You should assert that the first argument is not NULL and that the string it points to is not NULL. char *concat_strings (char *, char *); Convert both strings passed in as arguments into two lists, join the lists into one, and copy the elements of the new big list into a new string. Free the lists used and return a pointer the newly allocated string. This function takes two pointers to characters (strings), concatenates them, and returns a pointer to the new string. You should assert that the first argument is not NULL and that the string it points to is not NULL