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intermediate 8 min · Sep 21, 2026
Learn how the monotonic stack solves the next greater element problem in $O(n)$ time by tracing every push and pop for the array [2, 1, 2, 4, 3].
dsa monotonic stack algorithms arrays
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![Next greater of [2, 1, 2, 4, 3] overview diagram](/blogs/next-greater-element-explained-tracing-2-1-2-4-3-with-a-stack/diagrams/hero.svg)