112. Path Sum - cocoder39/coco39_LC GitHub Wiki

112. Path Sum

bool hasPathSum(TreeNode* root, int sum) {
        if(! root) {
            return false;//node who has only one child
        }
        if(! root->left && ! root->right) {   //check leave
            return root->val == sum;
        }
        return hasPathSum(root->left, sum-root->val) || hasPathSum(root->right, sum-root->val);
    }