LIFO and FIFO structures used in parsing, scheduling and buffering.
A stack is last-in-first-out (push, pop), used for function calls, undo and expression parsing. A queue is first-in-first-out (enqueue, dequeue), used for scheduling and BFS. Deques and circular buffers generalise them. Implementations use arrays or linked lists.
Balanced-parentheses checking uses a stack.
Stacks and queues enforce order of access, which is the basis of undo features, parsers, schedulers and message buffers.
LIFO and FIFO structures used in parsing, scheduling and buffering.
Stacks and queues enforce order of access, which is the basis of undo features, parsers, schedulers and message buffers.
When the most recent item must be handled first, such as function calls, undo history or depth-first search.
When items must be processed in arrival order, such as tasks, requests or messages.
Typical applications include implementing undo in an editor with a stack, processing print jobs in the order they arrive with a queue and checking balanced brackets in an expression with a stack.
Study "Sorting algorithms" first (topic 18 of 104 in Software & Computing). It covers the groundwork this topic builds on.
O(1) operations. Call stack. Producer-consumer queues.
Balanced-parentheses checking uses a stack.
The next topic is "Linked lists", which builds directly on this one.
It is classed as Beginner in Software & Computing (topic 19 of 104). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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