判断某数组是否是某二叉搜索树的后序遍历的结果

题目：

输入一个数组，判断该数组是不是某二叉搜索树的后序遍历结果。

解答：

public class Solution {

    public static void main(String[] args) {
        int[] array = {5,7,6,9,11,10,8};

        boolean b = verfiySequenceOfBST(array, 0, 6);
        System.out.println(b);
    }

    private static boolean verfiySequenceOfBST(int[] array, int start, int end) {
        if(array == null || start > end || start < 0 || end < 0) {
            return false;
        }

        if(start == end) {
            return true;
        }

        int root = array[end];
        for(; i <= end; i++) {
            if(array[i] > root) {
                break;
            }
        }

        int j = i;
        for(; j <= end; j++) {
            if(array[j] < root) {
                return false;
            }
        }

        boolean left = true;

        if(i > start) {
            left = verfiySequenceOfBST(array, start, i-1);
        }

        boolean right = true;

        if(i < end) {
            right = verfiySequenceOfBST(array, i, end-1);
        }

        return left&&right;

    }
}