621

class Solution {
public:
    int max(int a, int b){
        return (a > b) ? a:b;
    }

    int leastInterval(vector<char>& tasks, int n) {
        int maxCount, ans;
        maxCount = ans = 0;
        unordered_map<char, int> m;

        for(auto c: tasks){
            m[c]++;
            maxCount = max(maxCount, m[c]);
        }

        ans = (maxCount-1)*(n+1);
        for(auto c: m){
            if(c.second == maxCount) ans++;
        }
        ans = max(ans, tasks.size());
        return ans;
    }
};