剑指offer---二叉树的镜像2

非递归版本：

/*
struct TreeNode {
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
    TreeNode(int x) :
            val(x), left(NULL), right(NULL) {
    }
};*/
class Solution 
{
public:
    void Mirror(TreeNode *pRoot)
    {
        //用栈
        
        if(pRoot==NULL)
        {
            return;
        }
        
        stack<TreeNode*> jiedian;
        jiedian.push(pRoot);
        while(jiedian.size()!=0)
        {
            TreeNode* cur=jiedian.top();
            jiedian.pop();
            
            if(cur->right!=NULL||cur->left!=NULL)
            {
                TreeNode* temp=cur->left;
                cur->left=cur->right;
                cur->right=temp;
            }
            
            if(cur->left!=NULL)
            {
                jiedian.push(cur->left);
            }
            if(cur->right!=NULL)
            {
                jiedian.push(cur->left);
            }
        }
        
        
    }
};