[leetcode]@python 84. Largest Rectangle in Histogram

题目链接

https://leetcode.com/problems/largest-rectangle-in-histogram/

题目原文

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.

For example,

Given heights = [2,1,5,6,2,3],

return 10.

题目大意

给定一个包含小矩形高度的数组，返回这些小矩形覆盖区域的最大矩形的面积

解题思路

http://www.cnblogs.com/zuoyuan/p/3783993.html

代码

class Solution(object):
def largestRectangleArea(self, heights):
"""
:type heights: List[int]
:rtype: int
"""
stack = []
i = 0
area = 0

while i < len(heights):
if stack == [] or heights[i] > heights[stack[len(stack) - 1]]:
stack.append(i)
else:
cur = stack.pop()
if stack == []:
width = i
else:
width = i - stack[len(stack) - 1] - 1
area = max(area, width * heights[cur])
i -= 1
i += 1

while stack != []:
cur = stack.pop()
if stack == []:
width = i
else:
width = len(heights) - stack[len(stack) - 1] - 1
area = max(area, width * heights[cur])

return area