7. Monotonic Stack

PRO

Hard

Topics

Helpful tools to learn & understand

Visualize LogicActive Simulator

Watch key transitions, pointers, and variables update step-by-step.

Open

Check Solutions

Read clean, documented implementations across multiple patterns.

View Code

Thinkpad (Draw & Note)

Sketch diagrams on an infinite canvas and draft notes directly inline.

Draw

Example 1:

Input: heights = [2,1,5,6,2,3]

Output: 10

Explanation: The largest rectangle is formed by the bars with heights 5 and 6, having a width of 2, resulting in an area of 5 * 2 = 10 or 6 * 2 = 12. Considering the area to be width * height, the rectangle starts at 5 and ends before 2 (index 4) . Maximum area with height 6 and width one.

Example 2:

Input: heights = [2,4]

Output: 4

Explanation: The largest rectangle is the bar with height 4.

Constraints:

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Time Complexity

O(n)

Space Complexity