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# Selection Sort

This might not be the most efficient implementation of the selection sort algorithm. However, it is the one that closely matches how the algorithm is explained:

- Pick up the first card (if this was a deck of cards).
- Compare the card in your hand to each other card in turn
- If a smaller card is found, swap the cards (so the smaller card is now in your hand).
- When you get to the last card, put the card in your hand into a separate pile.
- Repeat steps 1-4 until there are no more cards in the original deck

## Create A Sequence

```
alist = [8,5,3,6,2,1,9,4,7]
alist
```

```
[8, 5, 3, 6, 2, 1, 9, 4, 7]
```

## Create A Selection Sort Algorithm

```
# Define a function that takes an unsorted list,
def selection_sort(alist):
# Create a new list containing the values from the inputed list
unsorted_sequence = alist[:]
# Create a list where we will place the sorted values
sorted_sequence = []
# While there are still values in the unsorted sequence:
while len(unsorted_sequence) > 0:
# For each value in the unsorted sequence,
for i, _ in enumerate(unsorted_sequence):
# Assume it is the smallest value
smallest_value_index = i
# Compare it which each other value in the unsorted list
for i, _ in enumerate(unsorted_sequence):
# If a smaller value is found
if unsorted_sequence[smallest_value_index] > unsorted_sequence[i]:
# Swap the two values so the new value is the one we think is the smallest
smallest_value_index, i = i, smallest_value_index
# When we get to the end of the sequence, remove the smallest valued card
smallest_value = unsorted_sequence.pop(smallest_value_index)
# And add it to our sequence of sorted values
sorted_sequence.append(smallest_value)
# Print the sorted sequence
print('Sorted sequence so far:', sorted_sequence)
```

```
# Run the selection sort
selection_sort(alist)
```

```
Sorted sequence so far: [1]
Sorted sequence so far: [1, 2]
Sorted sequence so far: [1, 2, 3]
Sorted sequence so far: [1, 2, 3, 4]
Sorted sequence so far: [1, 2, 3, 4, 5]
Sorted sequence so far: [1, 2, 3, 4, 5, 6]
Sorted sequence so far: [1, 2, 3, 4, 5, 6, 7]
Sorted sequence so far: [1, 2, 3, 4, 5, 6, 7, 8]
Sorted sequence so far: [1, 2, 3, 4, 5, 6, 7, 8, 9]
```