Find the minimum and maximum amount to buy all N candies

import java.util.*;

public class Solution {
    private int minCost = Integer.MAX_VALUE;
    private int maxCost = 0;
    
    private void permute(int[] cost, int[] indices, int start) {
        if (start == indices.length) {
            calculate(cost, indices);
            return;
        }
        
        for (int i = start; i < indices.length; i++) {
            swap(indices, start, i);
            permute(cost, indices, start + 1);
            swap(indices, start, i);
        }
    }
    
    private void swap(int[] arr, int i, int j) {
        int temp = arr[i];
        arr[i] = arr[j];
        arr[j] = temp;
    }
    
    private void calculate(int[] cost, int[] indices) {
        int totalCost = 0;
        boolean[] taken = new boolean[cost.length];
        
        for (int idx : indices) {
            if (!taken[idx]) {
                totalCost += cost[idx];
                taken[idx] = true;
                
                for (int j : indices) {
                    if (!taken[j] && cost[j] <= cost[idx]) {
                        taken[j] = true;
                        break;
                    }
                }
            }
        }
        
        minCost = Math.min(minCost, totalCost);
        maxCost = Math.max(maxCost, totalCost);
    }
    
    public int[] findMinMaxCost(int[] cost) {
        int n = cost.length;
        int[] indices = new int[n];
        for (int i = 0; i < n; i++) indices[i] = i;
        
        minCost = Integer.MAX_VALUE;
        maxCost = 0;
        permute(cost, indices, 0);
        
        return new int[]{minCost, maxCost};
    }
}

import java.util.*;

public class CandyCost {
    public int findMinimum(int[] cost) {
        int n = cost.length;
        Integer[] sorted = new Integer[n];
        for (int i = 0; i < n; i++) sorted[i] = cost[i];
        
        // Sort in descending order
        Arrays.sort(sorted, Collections.reverseOrder());
        
        int minCost = 0;
        int buy = 0, free = n - 1;
        
        while (buy <= free) {
            minCost += sorted[buy];
            buy++;
            free--;
        }
        
        return minCost;
    }
    
    public int findMaximum(int[] cost) {
        int n = cost.length;
        int[] sorted = cost.clone();
        
        // Sort in ascending order
        Arrays.sort(sorted);
        
        int maxCost = 0;
        int buy = 0, free = n - 1;
        
        while (buy <= free) {
            maxCost += sorted[buy];
            buy++;
            free--;
        }
        
        return maxCost;
    }
    
    public int[] findMinMax(int[] cost) {
        return new int[]{findMinimum(cost), findMaximum(cost)};
    }
    
    public static void main(String[] args) {
        CandyCost cc = new CandyCost();
        int[] cost = {3, 2, 1, 4};
        
        int[] result = cc.findMinMax(cost);
        System.out.println("Minimum: " + result[0] + ", Maximum: " + result[1]);
        
        // Example 2
        int[] cost2 = {1, 2, 3, 4, 5, 6, 7};
        int[] result2 = cc.findMinMax(cost2);
        System.out.println("Minimum: " + result2[0] + ", Maximum: " + result2[1]);
    }
}