621. 任务调度器

Q:

class Solution {
public:
    int leastInterval(vector<char>& tasks, int n) {
        map<char,int>dc;
        for(char c:tasks){
            dc[c]+=1;
        }
        vector<int>dic;
        for(auto pair:dc){
            dic.push_back(pair.second);
        }
        int cnt=0;
        make_heap(dic.begin(),dic.end());
        while(not dic.empty()){
            vector<int>temp;
            int i=0;
            while(not dic.empty() and i<n+1){
                temp.push_back(dic[0]);
                temp.back()-=1;
                pop_heap(dic.begin(),dic.end());
                dic.pop_back();
                ++i;
            }
            for (int x:temp){
                if (x){
                    dic.push_back(x);
                }
            }
            if (not dic.empty()){
                cnt+=n+1;
                push_heap(dic.begin(),dic.end());
            }
            else{
                cnt+=i;
                break;
            }
        }
        return cnt;
    }
};

class Solution {
public:
    int leastInterval(vector<char>& tasks, int n) {
        map<char,int> mp;
        for(char c:tasks){
            mp[c]+=1;
        }
        vector<int> dic;
        int cnt=0;
        for(auto pair:mp){
            dic.push_back(pair.second);
        }
        sort(dic.begin(),dic.end());
        while(not dic.empty()){
            int i=0,pos=dic.size()-1;
            while(pos-i>=0 and i<n+1){
                dic[pos-i]-=1;
                ++i;
            }
            sort(dic.begin(),dic.end());
            int j=0;
            while(j<=pos and dic[j]==0){
                ++j;
            }
            dic.erase(dic.begin(),dic.begin()+j);
            if(dic.empty()){
                cnt+=i;
            }
            else{
                cnt+=n+1;
            }
        }
        return cnt;
    }
};