public class Solution {
    
    boolean Judge(int [] a,int l,int r)
    {
        if(l>=r) return true;
        int i=r;
        while(i>l&&a[i-1]>a[r]) --i;
        
        for(int j=i-1;j>=l;--j)
        {
            if(a[j]>a[r]) return false;
        }
        
        return Judge(a,l,i-1)&&(Judge(a,i,r-1));
 
    }
    
    public boolean VerifySquenceOfBST(int [] sequence) {
        
        if(sequence.length==0) return false;
        return Judge(sequence,0,sequence.length-1);
    }
}