leetcode563二叉树的坡度

???????????д??鼴??,????????? leetcode OJ ????

int res;
int sum(struct TreeNode *root)
{
    if (!root)
        return 0;
    int left = sum(root->left);
    int right = sum(root->right);
    res += abs(left - right);
    return left + right + root->val;
}

int findTilt(struct TreeNode *root)
{
    res = 0;
    sum(root);
    return res;
}

????????????Global variable,???????????int res = 0,????findTilt?????в?????? res ????,leetcode ???н????????????????н???????.
????? leetcode ???????????????????,leetcode ???????ε????????????????????????н?????,??????????α????

testCases = {...} # ????????
testAnswers = {...} # leetcode?????????y??
i = 0
for each in testCases:
    if yourSolution's return != testAnswers[i]:
        return False
    i += 1

???????,?????????? res ?????testAnswers???б??,????????ε????п???,?????????????δ????,?????"????????μ????????????",??????????.
?????黹?????????????