题解 | #统计农场牛数量#
统计农场牛数量
https://www.nowcoder.com/practice/c18924a6debf437180d77baec91dc586
/** * struct TreeNode { * int val; * struct TreeNode *left; * struct TreeNode *right; * TreeNode(int x) : val(x), left(nullptr), right(nullptr) {} * }; */ class Solution { public: /** * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可 * * * @param root TreeNode类 * @return int整型 */ void countNum(TreeNode* root, int & count) { if (root == nullptr) return; count += 1; countNum(root->left, count); countNum(root->right, count); } int countNodes(TreeNode* root) { // write code here int count = 0; countNum(root, count); return count; } };