【leetcode】Array——Largest Rectangle in Histogram（84）

题目：

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.

For example,

Given heights =

[2,1,5,6,2,3]

,

return

10

.
思路：Stack

见链接：http://www.geeksforgeeks.org/largest-rectangle-under-histogram/

代码：

public class Solution {
public int largestRectangleArea(int[] height) {
int len = height.length;
Stack<Integer> s = new Stack<Integer>();
int maxArea = 0;
for(int i = 0; i <= len; i++){
int h = (i == len ? 0 : height[i]);
if(s.isEmpty() || h >= height[s.peek()]){
s.push(i);
}else{
int tp = s.pop();
maxArea = Math.max(maxArea, height[tp] * (s.isEmpty() ? i : i - 1 - s.peek()));
i--;
}
}
return maxArea;
}
}