Rabbits in Forest | Leetcode 781

class Solution {
public:
    int numRabbits(vector<int>& answers) {
        int n = answers.size();
        unordered_map<int,int> group_freq;
        int count = 0;
        
        //Insert all elements and count full_group_elements
        for(int ele: answers){
            if(ele==0)
                count += 1;
            else{
                group_freq[ele]++;
                if(group_freq[ele]==ele+1){
                    count += ele+1;
                    group_freq[ele]=0;
                }
            }
        }
        //Add leftover
        for(auto [group,freq]: group_freq)
            if(freq>0)
                count += group+1;
        
        return count;
    }
};
/*
//JAVA
import java.util.HashMap;

class Solution {
    public int numRabbits(int[] answers) {
        HashMap<Integer, Integer> groupFreq = new HashMap<>();
        int count = 0;
        
        for (int ele : answers) {
            if (ele == 0) {
                count += 1;
            } else {
                groupFreq.put(ele, groupFreq.getOrDefault(ele, 0) + 1);
                if (groupFreq.get(ele) == ele + 1) {
                    count += ele + 1;
                    groupFreq.put(ele, 0);
                }
            }
        }
        
        for (int key : groupFreq.keySet()) {
            int freq = groupFreq.get(key);
            if (freq > 0) {
                count += key + 1;
            }
        }
        
        return count;
    }
}

#Python
from collections import defaultdict

class Solution:
    def numRabbits(self, answers: List[int]) -> int:
        group_freq = defaultdict(int)
        count = 0
        
        for ele in answers:
            if ele == 0:
                count += 1
            else:
                group_freq[ele] += 1
                if group_freq[ele] == ele + 1:
                    count += ele + 1
                    group_freq[ele] = 0
        
        for group, freq in group_freq.items():
            if freq > 0:
                count += group + 1
        
        return count
*/