LeetCode/112_path_sum at master · KnowledgeCenterYoutube/LeetCode · GitHub

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Leetcode 112 : Path Sum
Detailed video explanation : https://youtu.be/7gsJjnnV_8E
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C++:
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/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    bool hasPathSum(TreeNode* root, int targetSum) {
        if(!root) return false;
        if(!root->left && !root->right) return (targetSum == root->val);
        bool pathSumExists = false;
        if(root->left) pathSumExists = hasPathSum(root->left, targetSum-root->val);
        if(root->right) pathSumExists = pathSumExists || hasPathSum(root->right, targetSum-root->val);

        return pathSumExists;
    }
};