# Function to sort a list containing only 0s and 1s
def sort_binary_list(arr):
left = 0 # Index to track the left side
right = len(arr) - 1 # Index to track the right side
while left < right:
# If the left index is at 0, move it forward
if arr[left] == 0:
print(f"left: {left}")
left += 1
# If the right index is at 1, move it backward
elif arr[right] == 1:
print(f"right: {right}")
right -= 1
# If left is 1 and right is 0, swap them
else:
arr[left], arr[right] = arr[right], arr[left]
print(f"swap() left: {left} right: {right}")
left += 1
right -= 1
# Input: Binary list
arr = [1, 0, 1, 0, 1, 0, 0, 1, 0]
# Sort the binary list
sort_binary_list(arr)
# Output the sorted list
print("Sorted list:", *arr)
"""
run:
swap() left: 0 right: 8
left: 1
right: 7
swap() left: 2 right: 6
left: 3
swap() left: 4 right: 5
Sorted list: 0 0 0 0 0 1 1 1 1
"""
