I have a heapsort function which i've used to sort a list of integers. How do I adapt this function to sort a list of strings alphbetically?

My sort function is:

Code:int temp, item, j; for(int k=i-1; k>0; k--) { for(int i=0; i<=k; i++) { item=value[i].first_name; j=i/2; while (j>0 && value[j].first_name<item) { value[i].first_name=value[j].first_name; i=j; j=j/2; } value[i].first_name=item; } temp=value[1].first_name; value[1].first_name=value[k].first_name; value[k].first_name=temp; }