标签：rectangle style present sha dex width pop show nbsp
Given n non-negative integers representing the histogram‘s bar height where the width of each bar is 1, find the area of largest rectangle in the histogram.
Above is a histogram where width of each bar is 1, given height = [2,1,5,6,2,3].
The largest rectangle is shown in the shaded area, which has area = 10 unit.
Example:
Input: [2,1,5,6,2,3] Output: 10
Solution 1: O(N^2) LTE
class Solution(object): def largestRectangleArea(self, heights): """ :type heights: List[int] :rtype: int """ if not heights: return 0 res = -1 for i, height in enumerate(heights): min_height = height res = max(res, min_height) for j in range(i + 1, len(heights)): min_height = min(min_height, heights[j]) res = max(res, (j - i + 1) * min_height) return res
Solution 2: O(N)
class Solution(object): def largestRectangleArea(self, heights): """ :type heights: List[int] :rtype: int """ if not heights: return 0 res, index = 0, 0 stack = [] while index <= len(heights): cur = 0 if index == len(heights) else heights[index] if not stack or cur >= heights[stack[-1]]: stack.append(index) index += 1 else: height = heights[stack.pop()] # make sure left and right index are correct right = index - 1 left = 0 if not stack else stack[-1] + 1 res = max(res, (right - left + 1) * height) return res
[LC] 84. Largest Rectangle in Histogram
标签：rectangle style present sha dex width pop show nbsp
原文地址：https://www.cnblogs.com/xuanlu/p/11828789.html
