Invert a binary tree.
4 / 2 7 / \ / 1 3 6 9to
4 / 7 2 / \ / 9 6 3 1Trivia:
Google: 90% of our engineers use the software you wrote (Homebrew), but you can’t invert a binary tree on a whiteboard so fuck off.
class Solution {
public:
TreeNode* invertTree(TreeNode* root) {
if(root==NULL) return NULL;
deque<TreeNode*> qu;
qu.push_front(root);
while(!qu.empty())
{
TreeNode* node=qu.front();
TreeNode* left=node->left;
node->left=node->right;
node->right=left;
qu.pop_front();
if(node->left)
qu.push_front(node->left);
if(node->right)
qu.push_front(node->right);
}
return root;
}
};class Solution {
public:
TreeNode* invertTree(TreeNode* root) {
if(root==NULL) return NULL;
TreeNode* left=root->left;
TreeNode* right=root->right;
root->left=invertTree(right);
root->right=invertTree(left);
return root;
}
};
原文：http://blog.csdn.net/sinat_24520925/article/details/46509115