求二叉树最大最小深度

public int maxDepth(TreeNode root) {
        if(root==null){
            return 0;
        }
        return 1+Math.max(maxDepth(root.left),maxDepth(root.right));
    }

int minDepth(TreeNode *root) {
        if(root == NULL)
            return false;

        if(root->left == NULL) return minDepth(root->right) + 1;
        if(root->right == NULL) return minDepth(root->left) + 1;

        int leftDepth = minDepth(root->left);
        int rightDepth = minDepth(root->right);

        return leftDepth < rightDepth ? (leftDepth + 1) : (rightDepth + 1);
    }