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Use List as Stack (LIFO)

Zero-dependency Python snippets for using a list as a stack (Last-In, First-Out) with the standard library.

4 snippets available in this sub-category.

Simple

Push and pop with list

stack list push pop LIFO data-structures

Use list append() and pop() for stack operations

stack = []
stack.append(1)  # Push
stack.append(2)
stack.append(3)
print(stack)  # [1, 2, 3]

item = stack.pop()  # Pop
print(item)  # 3
print(stack)  # [1, 2]

Notes

  • append() adds to the end (top of stack)
  • pop() removes from the end (top of stack)

Peek at top of stack

stack peek list data-structures

Access the top element without removing it

stack = [1, 2, 3]
top = stack[-1]
print(top)  # 3

Notes

  • Use stack[-1] to peek at the top
  • Raises IndexError if stack is empty

Complex

Stack with error handling

stack error-handling safe data-structures

Safe pop with empty stack check

def safe_pop(stack):
    if stack:
        return stack.pop()
    else:
        print("Stack is empty!")
        return None


stack = []
safe_pop(stack)  # Prints warning, returns None

Notes

  • Always check if stack is not empty before popping

Stack size and clear

stack size clear list data-structures

Get stack size and clear stack

stack = [1, 2, 3]
print(len(stack))  # 3
stack.clear()
print(stack)  # []

Notes

  • len(stack) for size, clear() to empty

🔗 Cross Reference

🏷️ Tags

stack, list, push, pop, peek, size, clear, LIFO, data-structures

📝 Notes

  • Python lists are efficient for stack operations
  • For thread-safe or multi-producer/consumer stacks, use queue.LifoQueue