[2016/11/17]翻转二叉树

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.

struct TreeNode* invertTree(struct TreeNode* root) {
struct TreeNode* p;
if(!root)
return NULL;
else{
p = root -> left;
root -> left = root -> right;
root -> right = p;
}
invertTree(root -> left);
invertTree(root -> right);
return root;
}