What is the result of evaluating the prefix expression '-+5*234'?
17
7
-7
-17
If you represent an arithmetic expression in postfix notation using a stack, what operation would you perform when encountering an operand (a number)?
Push the operand onto the stack.
Ignore the operand.
Check if the stack is empty.
Pop the top two elements from the stack, perform the operation, and push the result back onto the stack.
In maze-solving algorithms, how does the use of a stack differ between depth-first search (DFS) and breadth-first search (BFS)?
DFS uses a stack only if the maze is solvable, while BFS always uses a queue.
Both DFS and BFS use stacks identically; the difference lies in how they mark visited nodes.
DFS uses a stack to explore as deeply as possible before backtracking, while BFS uses a queue to explore all neighbors at a given level.
BFS uses a stack to prioritize unexplored paths, while DFS uses a queue to systematically explore all directions.
In a stack implemented using a linked list, where does the 'push' operation add the new element?
It depends on the data being inserted.
At a specific index in the linked list.
At the beginning of the linked list.
At the end of the linked list.
Which of the following stack operations has a time complexity of O(1) in both array-based and linked list-based implementations?
All of the above
Push
Peek
Pop
In a stack implemented using a singly linked list, which end of the list typically represents the top of the stack?
Middle
It can be either the head or the tail, depending on the implementation.
Tail
Head
Which real-life scenario most accurately reflects the LIFO (Last In First Out) principle of a stack data structure?
A tree of files and folders on a computer.
A stack of plates on a table.
A list of tasks sorted by priority.
A queue of people waiting for a bus.
What is the primary difference between 'pop' and 'peek' operations on a stack?
'Pop' retrieves the top element's value, while 'peek' removes it from the stack.
'Pop' removes the top element, while 'peek' only retrieves its value without removing it.
'Pop' and 'peek' are interchangeable terms for the same operation.
'Pop' is used for stacks, while 'peek' is used for queues.
In postfix evaluation, what action is taken when an operand is encountered?
It is pushed onto the stack.
It is immediately evaluated.
It is ignored.
It triggers the evaluation of operators on the stack.
During the infix to postfix conversion of the expression 'A+B*C-D/E', which operator would be pushed onto the stack first?
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