How does Python insertion sort work?

Question

Here\'s a Python implementation of insertion sort, I tried to follow the values on paper but once the counting variable i gets bigger than len(s) I don\'t know what to do, h

Answer 1

Consider [3, 2, 1]

The loop starts with 3. Since it is the first item in the list there is nothing else to do.

[3, 2, 1]

The next item is 2. It compares 2 to 3 and since 2 is less than 3 it swaps them, first putting 3 in the second position and then placing 2 in the first position.

[2, 3, 1]

The last item is 1. Since 1 is less than 3 it moves 3 over.

[2, 3, 3]

Since 1 is less than 2 it swaps moves 2 over.

[2, 2, 3]

Then it inserts 1 at the beginning.

[1, 2, 3]