Leecode路径相关 题目

class Solution {
public:
    int sumNumbers(TreeNode* root) {
        if(!root)return 0;
        dfs(root,root->val);
        return res;
    }
private:
    int res = 0;
    void dfs(TreeNode* root,int cur){
        if(!root) return ;
        if(!root->left && !root->right){
            res+=cur;
            return;
        }
        if(root->left)dfs(root->left, cur*10+root->left->val);
        if(root->right)dfs(root->right,cur*10+root->right->val);
    }
};

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class Solution {
public:
    vector<string> binaryTreePaths(TreeNode* root) {
        if(!root) return ans;
        dfs(root,to_string(root->val),ans);
        return ans;
    }
private:
    string curr;
    vector<string> ans;
    void dfs(TreeNode* root,string curr, vector<string>& ans){
        if(!root) return ;
        if(!root->left && !root->right){
            ans.push_back(curr);
            return ;
        }
        if(root->left) dfs(root->left,curr+"->"+to_string(root->left->val),ans);
        if(root->right) dfs(root->right,curr+"->"+to_string(root->right->val),ans);
    }
};