Recursive Selection Sort

Question

I'm trying to write a recursive selection sort, and I'm really confused, and its really hard to be to track why this doesn't work. If anyone could tell me where the problem is, that would be great!

Here's my code

def selectionSortRecursive(lis, minIndex = 0):
    if minIndex - 1 == len(lis):
        return lis
    minValueIndex = minIndex #Assigns the very first item in the list as the minimum value index
    for i in range (minIndex + 1, len(lis)):
        if lis[i] < lis[minValueIndex]: #if any item is less than min value, its index gets assigned the minimum value
            minValueIndex = i
    lis[minIndex], lis[minValueIndex] = lis[minValueIndex], lis[minIndex] #After you go through the list, you switch the smallest item into the minimum index, which starts off being 0
    lis = selectionSortRecursive(lis, minIndex+1) #now we're gonna sort the list at the next min
    return lis

Answer 1

Please try this modification:

def selectionSortRecursive(lis, minIndex = 0):
    if minIndex - 1 == len(lis):
        return lis
    minValueIndex = minIndex #Assigns the very first item in the list as the minimum value index
    for i in range (minIndex + 1, len(lis)):
        if lis[i] < lis[minValueIndex]: #if any item is less than min value, its index gets assigned the minimum value
            lis[minValueIndex], lis[i] = lis[i], lis[minValueIndex] #After you go through the list, you switch the smallest item into the minimum index, which starts off being 0
    lis = selectionSortRecursive(lis, minIndex+1) #now we're gonna sort the list at the next min
    return lis

Answer 2

Try this.

static int maxIndex;
    public static void selectionSort(Object[] source, int fromIndex, int endIndex){
        if(endIndex==fromIndex){
            return;
        }
        else{
            if(((Comparable) source[fromIndex]).compareTo(source [maxIndex])>0){
                maxIndex=fromIndex;
            }
            bubbleSort(source,fromIndex+1,endIndex);
        }
        Object temp=source[fromIndex];
        source[fromIndex]=source[maxIndex];
        source[maxIndex]=temp;
        bubbleSort(source,fromIndex,endIndex-1);
    }