Look for these signals in the problem:
- "Matching" brackets, parentheses, or tags: Push opening symbols, pop and match when closing symbols appear.
- "Most recent" or "undo" functionality: Stack remembers recent items for reversal or backtracking.
- Expression evaluation (postfix/infix): Operands go on stack, operators pop and compute.
- "Nested" structures: When processing nested elements, stack tracks the nesting level and context.
- Converting recursion to iteration: Explicit stack replaces implicit call stack for iterative solutions.