Thread: Selection Sort

I'd greatly appreciate it if someone could explain for me exactly how the selection sort algorithm works.

Code:

for (startScan = 0; startScan < (elems - 1); startScan++)
{
	minIndex = startScan;
	minValue = array[startScan];

	for (int index = startScan + 1; index < elems; index++)
	{
		if (array[index] < minValue)
		{
			minValue = array[index];
			minIndex = index;
		}
	}
	array[minIndex]  = array[startScan];
	array[startScan] = minValue;
}

The relationship between

Code:

minIndex = startScan;
minValue = array[startScan];

and

Code:

array[minIndex]  = array[startScan];
array[startScan] = minValue;

is especially confusing me.

It really is good practice for you to be able to work through this on your own, otherwise algorithms will always be confusing to you. I'd suggest taking a piece of paper, creating a random unsorted array like say {10,5,7,1,0,14,12,2} and working through the sort one line at a time keeping track of all of the variables. I guarantee that in only a couple of times through the loop you will understand exactly what those lines are doing, and you'll learn a heck of a lot more than by having someone explain it to you.