Monotonic Decreasing Stack

The Monotonic Decreasing Stack technique is applied when tackling problems characterized by specific invariants in the problem state or constraints:

• Core Strategy: Maintain a stack that only ever decreases, popping elements when a larger one arrives to find next-greater relationships.
• When to use: Look for opportunities where repeated re-computation can be replaced by maintaining monotonic properties, state windows, or relational pointers.
• Interview Signal: Demonstrating this pattern shows mastery of Stack foundations, reducing worst-case algorithmic complexity.