// 以每一柱为高向两边延伸

public class LargestRectangleArea {

    int max = 0;

    public int largestRectangleArea(int[] heights) {

        for (int i=0;i<heights.length;i++) {

            int height = heights[i];

            int left = i;

            int right = i;

            while(--left>=0) {

                if (heights[left] < heights[i]){

                    break;

                }

            }

            while(++right<=heights.length-1) {

                if (heights[right] < heights[i]){

                    break;

                }

            }

            int length = right - left - 1;

            if (max < length*height) {

                max = length*height;

            }

        }

        return max;

    }

}