Question

Can you tell me what’s wrong with my method? I ends up putting the same thing everywhre and it’s actually not sorting.

void sortArrays(){

    int i, j;



    for(i=0; i<counter; i++){



        for( j=0; j<i; j++){

            if( strcmp(title_arr[i], title_arr[j]) < 0){

                char* title_temp = title_arr[i];

                title_arr[j] = title_temp;





            }

        }

    }

Answer 1

This:

char* title_temp = title_arr[i];

title_arr[j] = title_temp;

Is equivalent to:

title_arr[j] = title_arr[i];

You never swap them, you just copy one to the other. You should add this line:

title_arr[i] = title_arr[j];

In between the two. That way, you’ll overwrite [i] with [j], but _temp still holds the old value of [i], so you can copy that value into [j], thus swapping them.

I suppose it’s also a time for a lesson on algorithms. Your algorithm is known as a “bubble sort” algorithm. It is known for it’s simplicity, but in a realistic setting it is known for it’s inefficiency (the technical term is “teh sux”, and the real technical term is O(n^2) (“N squared”) performance). Some more common (and more efficient) algorithms include Quicksort, merge sort, and Heapsort, among many others. For more about measuring algorithmic scalability, see the article on Big Oh notation.*

But, as vava pointed out in a comment, unless your assignment is to write your own sorting function, you’re going to get better performance with qsort (in C) or std::sort (in C++).

int mystrsort(const void *a, const void *b)
{
    return strcmp(*(const char **)a, *(const char **)b);
}

// later:
qsort(title_arr, sizeof title_arr / sizeof(char *), sizeof(char *), mystrsort);

I’m not going to stab at std::sort, but it’s going to work about the same (perhaps easier).**

*Note that anyone who likes is free to change these Wikipedia links to Stack Overflow links. It would be better to link to SO, I just linked to Wikipedia because I knew how to find the info I needed faster.
**Note that anyone who likes is free to add a std::sort example. I’m just not sufficiently familiar with C++.