104 求二叉树最大深度.cpp

class Solution {
public:
	int maxDepth(TreeNode* root) {
		int depth=0;
		
		if (!root)
			return depth;
		queue<TreeNode*> level;
		level.push(root);
		while (!level.empty())
		{
			depth++;
			int n=level.size();
			for (int i = 0; i <n ; ++i)
			{
				TreeNode* node=level.front();
				level.pop();
				if (node->left)
					level.push(node->left);
				if (node->right)
					level.push(node->right);
			}
		}

		return depth;
	}
};




class Solution {
public:
	int maxDepth(TreeNode* root) {
		return root?1+max(maxDepth(root->left),maxDepth(root->right)):0;
	}
};