Leetcode•Sep 07, 2025
Largest Rectangle in Histogram
Hazrat Ali
Leetcode
Given an array of integers heights representing the histogram's bar height where the width of each bar is 1, return the area of the largest rectangle in the histogram.
Example 1:
Input: heights = [2,1,5,6,2,3] Output: 10 Explanation: The above is a histogram where width of each bar is 1. The largest rectangle is shown in the red area, which has an area = 10 units.
Example 2:
Input: heights = [2,4] Output: 4
Solution
/**
* @param {number[]} heights
* @return {number}
*/
const largestRectangleArea = heights => {
const n = heights.length;
const stack = new Stack();
let max = 0;
for (let i = 0; i <= n; i++) {
while (!stack.isEmpty() && (i === n || heights[i] < heights[stack.peek()])) {
const height = heights[stack.pop()];
const width = stack.isEmpty() ? i : i - 1 - stack.peek();
max = Math.max(max, width * height);
}
stack.push(i);
}
return max;
};