Question
A data structure allows insertion and deletion only from
one end. Which of the following best describes its use case in real-world scenarios?Solution
The described data structure is a stack, which operates on the Last In, First Out (LIFO) principle. Stacks are widely used in backtracking scenarios, such as in games or puzzles, where previous states are stored so the system can revert to them when required. For instance, in a maze-solving game, the stack keeps track of visited nodes. When a dead-end is reached, the program "backtracks" to the previous node stored at the top of the stack. This makes the stack an ideal structure for handling such recursive or reversible tasks efficiently. Why Other Options are Incorrect: 1. Parsing expressions in a compiler: While stacks are used in parsing, it’s primarily for operator precedence or syntax trees rather than directly describing "insertion and deletion from one end." The focus here is less about backtracking and more about parsing order. 2. Managing a printer queue in a network: Printer queues follow a First In, First Out (FIFO) principle, making queues, not stacks, suitable for this scenario. 3. Scheduling processes in a multiprogramming OS: Process scheduling is usually handled by priority queues or other data structures like heaps for optimal resource allocation. 4. Priority queue management in heaps: Heaps provide efficient handling for priorities, but they do not follow the strict LIFO behavior described in the question.
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