判断二叉树的后续遍历序列
bool VerifySquenceOfBST(vector<int> sequence) {
if(sequence.empty())
return false;
int len =sequence.size();
int i=0;
int root=sequence[len-1];
vector<int> left;
vector<int> right;
for(;i<len-1&&sequence[i]<root;i++)left.push_back(sequence[i]); //i<len-1 因为[len-1]是root
for(;i<len-1&&sequence[i]>root;i++)right.push_back(sequence[i]);
if(i==len-1)
return (left.size()?VerifySquenceOfBST(left):1) //要判断子树是否为空
&&(right.size()?VerifySquenceOfBST(right):1);
else
return false;
}