Answer
See the explanation
Work Step by Step
To sort a stack in ascending order without using any additional data structure, we can use a simple algorithm known as "Stack Sorting". Here's a program in Python that implements this algorithm:
```python
def sort_stack(stack):
if not stack:
return stack
temp_stack = []
while stack:
# Remove the top element from the original stack
temp = stack.pop()
# Move the elements from the temporary stack to the original stack
while temp_stack and temp_stack[-1] > temp:
stack.append(temp_stack.pop())
# Push the current element to the temporary stack
temp_stack.append(temp)
return temp_stack
```
Let's break down the algorithm step by step:
1. Create an empty temporary stack to store the sorted elements.
2. While the original stack is not empty, do the following:
- Pop the top element from the original stack and store it in a variable called `temp`.
- While the temporary stack is not empty and the top element of the temporary stack is greater than `temp`, pop elements from the temporary stack and push them back to the original stack.
- Push `temp` to the temporary stack.
3. Once the original stack is empty, the temporary stack will contain the sorted elements in ascending order.
4. Return the temporary stack.
The time complexity of this algorithm is O(n^2), where n is the number of elements in the stack.
