Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the **longest** path between any two nodes in a tree. This path may or may not pass through the root.

**Example:**
Given a binary tree

```
1
/ \
2 3
/ \
4 5
```

Return **3**, which is the length of the path [4,2,1,3] or [5,2,1,3].

**Note:** The length of path between two nodes is represented by the number of edges between them.

**Solution:**

MAX-DEPTH

```
class Solution {
public:
int depth(TreeNode* root){
if(root == NULL) return 0;
return max(depth(root->left), depth(root->right))+1;
}
int diameterOfBinaryTree(TreeNode* root) {
if(root == NULL) return 0;
return max(max(diameterOfBinaryTree(root->left), diameterOfBinaryTree(root->right)), depth(root->left)+depth(root->right));
}
};
```