递归分治,不断划分,从后向前找第一个比最后一个大的,然后用他划分,分成两个,继续递归。

public class Solution {
    public boolean VerifySquenceOfBST(int [] sequence) {
        if(sequence.length == 0){
            return false;
        }
        return check(sequence,0,sequence.length-1);
    }
    public boolean check(int[] we,int low,int high){
        if(low >= high ){
            return true;
        }
        int li = high-1;
        for(;we[li] > we[high];){
            li--;
            if(li == 0){
                break;
            }
        }
        for(int i =0;i<li;i++){
            if(we[i]>we[high]) 
                return false;
        }
        return check(we,0,li) && check(we,li+1,high-1);
    }
}