selection sort

[bluegray]

Two questions here
1.When i run this selection sort function it is not sorting the whole vector. It is only sorting the first few

2.When i compile this i get a compiler warning "warning: comparison between signed and unsigned integer expressions". It is coming form my for loops. Is this something that can cause problems down the road and how could i fix this or write this function better?

/*Selection sort will sort the vectors in ascending order*/
void selSort(vector<int>& v)
{
        int temp, min;

        for( int i = 0; i < v.size(); i++){
                min = i;
                for (int j = 1; j < v.size(); j++){
                        if (v[j] < v[min])
                        min = j;
                }
                temp = v[i];
                v[i] = v[min];
                v[min] = temp;
        }
}//end selection sort

[jpeg]

v.size returns an unsigned int. I don't think it should cause a problem, but I can't say for sure.

In regards to your first question, print out vector at different points and make sure you aren't losing any values. I vaguely remember a similar problem I had when I was doing something like this and I was actually overwriting values rather than sorting them. I ended up with an array of about half the size I started with.

[helios]

It will only cause trouble when size() returns a value larger that INT_MAX (constant #define'd in climits). This value is usually no less than 2^31-1.

Your swap doesn't verify that min!=¡, so you might be swapping an element with itself at times.

[jsmith]

The problem is that your inner for-loop is wrong, because it is considering too many elements. You know after the Nth iteration of the outer loop that the first N elements are sorted so the inner loop must not consider those, as they are guaranteed to be less than v[min].

[helios]

Oh, look at that. I missed it.
The for i loop is also too long. It should be i<v.size()-1