原题题目

---

代码实现（首刷自解）

class Solution {
public:
    int minDeletions(string s) {
        int ret = 0;
        vector<int> v(26,0);
        for(const auto& chr:s)  ++v[chr-'a'];

        sort(v.begin(),v.end(),greater<int>());

        int temp = v[0];
        for(int i=1;i<v.size();++i)
        {
            if(!v[i])   break;
            if(temp <= v[i])
            {
                temp = max(temp-1,0);
                ret += (v[i] - temp); 
            }
            temp = min(temp,v[i]);
        }

        return ret;
    }
};