Monistus

import java.util.Scanner;
import java.util.ArrayList;

public class monistus {
    
    public static boolean onNumero(String string){
        try {
            int Value = Integer.parseInt(string);
            return true;
        } catch (NumberFormatException e){
            
        }
        return false;
    }
    public static void main(String[] args) {
        Scanner lukija = new Scanner(System.in);
        String syote = lukija.nextLine();

        String[] syotteet = syote.split("");
        ArrayList<String> syoteLista = new ArrayList<String>();
        
        for (String s : syotteet){
            syoteLista.add(s);
        }
        //System.out.println(syoteLista);

        for (int i = 0; i < syoteLista.size(); i++) {
            if (onNumero(syoteLista.get(i))) {
                //System.out.println(syoteLista.get(i));
                int l = (Integer.parseInt(syoteLista.get(i)));
                syoteLista.remove(i);
                //System.out.println(syoteLista);
                for (int j = 0; j < l; j++){
                    syoteLista.add((i+l+j), syoteLista.get(i+j));
                    //System.out.println(j);
                }
                i--;
            }
        }
        for (String a : syoteLista) {
            System.out.print(a);
        }
    }
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: ACCEPTED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 2

Verdict: TIME LIMIT EXCEEDED