Highest Score

• Time : $O(n)$
• Space : $O(n)$

int Solution::highestScore(vector<vector<string>> &A) {
    unordered_map<string, int> sum, cnt;
    for(auto a : A) {
        int score = stoi(a[1]);
        sum[a[0]] += score;
        cnt[a[0]] += 1;
    }
    int res = 0;
    for(auto& [k,v] : sum) {
        res = max(res, v / cnt[k]);
    }
    return res;
}