Minimum Number of Groups to Create a Valid Assignment solution and explanation

from collections import Counter

def min_boxes(balls):
    frequency = Counter(balls)
    max_balls = max(frequency.values())
    boxes_needed = max_balls
    return boxes_needed

# Example usage
balls = [3, 2, 3, 2, 3]
print(min_boxes(balls))  # Output: 2

import java.util.HashMap;
import java.util.Map;

public class Solution {
    public int minBoxes(int[] balls) {
        Map<Integer, Integer> frequency = new HashMap<>();
        for (int ball : balls) {
            frequency.put(ball, frequency.getOrDefault(ball, 0) + 1);
        }
        int max_balls = 0;
        for (int count : frequency.values()) {
            max_balls = Math.max(max_balls, count);
        }
        return max_balls;
    }

    public static void main(String[] args) {
        Solution sol = new Solution();
        int[] balls = {3, 2, 3, 2, 3};
        System.out.println(sol.minBoxes(balls));  // Output: 2
    }
}

#include <iostream>
#include <unordered_map>
#include <algorithm>
using namespace std;

int minBoxes(vector<int>& balls) {
    unordered_map<int, int> frequency;
    int max_balls = 0;
    for (int ball : balls) {
        frequency[ball]++;
        max_balls = max(max_balls, frequency[ball]);
    }
    return max_balls;
}

int main() {
    vector<int> balls = {3, 2, 3, 2, 3};
    cout << minBoxes(balls) << endl; // Output: 2
    return 0;
}

using System;
using System.Collections.Generic;

public class Solution {
    public int MinBoxes(int[] balls) {
        Dictionary<int, int> frequency = new Dictionary<int, int>();
        int max_balls = 0;
        foreach (int ball in balls) {
            if (!frequency.ContainsKey(ball)) {
                frequency[ball] = 0;
            }
            frequency[ball]++;
            max_balls = Math.Max(max_balls, frequency[ball]);
        }
        return max_balls;
    }

    public static void Main(string[] args) {
        Solution sol = new Solution();
        int[] balls = new int[] {3, 2, 3, 2, 3};
        Console.WriteLine(sol.MinBoxes(balls));  // Output: 2
    }
}

function minGroupsForValidAssignment(nums: number[]): number {
    const cnt: Map<number, number> = new Map();
    for (const x of nums) {
        cnt.set(x, (cnt.get(x) || 0) + 1);
    }
    for (let k = Math.min(...cnt.values()); ; --k) {
        let ans = 0;
        for (const [_, v] of cnt) {
            if (((v / k) | 0) < v % k) {
                ans = 0;
                break;
            }
            ans += Math.ceil(v / (k + 1));
        }
        if (ans) {
            return ans;
        }
    }
}

func minGroupsForValidAssignment(nums []int) int {
	cnt := map[int]int{}
	for _, x := range nums {
		cnt[x]++
	}
	k := len(nums)
	for _, v := range cnt {
		k = min(k, v)
	}
	for ; ; k-- {
		ans := 0
		for _, v := range cnt {
			if v/k < v%k {
				ans = 0
				break
			}
			ans += (v + k) / (k + 1)
		}
		if ans > 0 {
			return ans
		}
	}
}

use std::collections::HashMap;

impl Solution {
    pub fn min_groups_for_valid_assignment(nums: Vec<i32>) -> i32 {
        let mut cnt: HashMap<i32, i32> = HashMap::new();

        for x in nums.iter() {
            let count = cnt.entry(*x).or_insert(0);
            *count += 1;
        }

        let mut k = i32::MAX;

        for &v in cnt.values() {
            k = k.min(v);
        }

        for k in (1..=k).rev() {
            let mut ans = 0;

            for &v in cnt.values() {
                if v / k < v % k {
                    ans = 0;
                    break;
                }

                ans += (v + k) / (k + 1);
            }

            if ans > 0 {
                return ans;
            }
        }

        0
    }
}