Kolikot

import java.util.Arrays;
import java.util.Scanner;

public class Main
{
    static int[] coinValues;
    
    public static void main(String[] args)
    {
        Scanner inputTaker = new Scanner(System.in);
        
        int amountOfCoins = inputTaker.nextInt();
        inputTaker.nextLine();
        String coinsString = inputTaker.nextLine();
        
        coinValues = new int[amountOfCoins];
        
        /*Now the input is handled into an array*/
        String[] coinsStringArray = coinsString.split(" ");
        for(int i = 0; i < amountOfCoins; i++)
        {
            coinValues[i] = Integer.parseInt(coinsStringArray[i]);
        }
        
        Arrays.sort(coinValues);
        
        /*Now begins the actual calculation for the first unpresentable number*/
        int firstCoinValuesIndex = 0;
        
        /*i tells the number that is going to be examined - whether or not it can
        be expressed as a sum of coins*/
        for(int i = 1; true; i++)
        {
            //This prevents array-out-of-bounds -stuff
            if(firstCoinValuesIndex == amountOfCoins)
            {
                System.out.println(i);
                break;
            }
            
            int firstCoinValue = coinValues[firstCoinValuesIndex];
            if(firstCoinValue >= 1 && firstCoinValue <= i)
            {
                i += (firstCoinValue - 1);
                coinValues[firstCoinValuesIndex] = 0;
                firstCoinValuesIndex++;
            }
            else
            {
                System.out.println(i);
                break;
            }
        }
    }
    
    public static int firstIndexOf(int numberSearched, int someIndex)
    {
        int firstIndex = someIndex;
        for(int i = someIndex - 1; true; i--)
        {
            try
            {
                if(coinValues[i] == numberSearched) firstIndex = i;
                else return firstIndex;
            }
            catch(Exception e)
            {
                return firstIndex;
            }
        }
    }
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: WRONG ANSWER

Test 16

Group: 3

Verdict: ACCEPTED