Python
def selectionSort(alist):
    for fillslot in range(len(alist)-1,0,-1):
        positionMax = 0
        for location in range(1,fillslot+1):
            if alist[location] > alist[positionMax]:
                positionMax = location
        temp = alist[fillslot]
        alist[fillslot] = alist[positionMax]
        alist[positionMax] = temp
        
alist = [54,26,93,17,77,31,44,55,20]
selectionSort(alist)
print(alist)
[17, 20, 26, 31, 44, 54, 55, 77, 93]

explain my code
Your code implements the selection sort algorithm, which sorts a list in ascending order. Here's a breakdown of how it works:

1. **Function Definition**: The function `selectionSort` takes a list `alist` as an argument.

2. **Outer Loop**: The outer loop iterates from the last index of the list down to the first index (`fillslot`), indicating the current position where the maximum element will be placed.

3. **Finding Maximum**: Inside the outer loop, `positionMax` is initialized to 0. The inner loop iterates through the unsorted portion of the list (from index 1 to `fillslot`). It compares each element with the current maximum (`alist[positionMax]`). If a larger element is found, `positionMax` is updated to that index.

4. **Swapping Elements**: After finding the maximum element in the unsorted portion, the code swaps it with the element at the `fillslot` index. This places the maximum element in its correct position.

5. **Final Output**: After all iterations, the list `alist` is sorted in ascending order. The sorted list is printed.

The final output of the code is the sorted list: `[17, 20, 26, 31, 44, 54, 55, 77, 93]`.