Pakkaus

import java.util.Scanner;
 
/**
 *
 * @author Roni Juntunen
 */
 
public class Pakkaus {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        String in = input.next(); //luetaan parametrit merkkijonoon
        String out = ""; //varataan muuttuja tulokselle
        Integer index = 0; //ilmaisee merkkijonon luennan sijainnin
        Integer end = in.length(); //merkkijonon pituus
        String part = ""; //valiaikainen merkkijono kertoimen lukemiseen, tarvitaan yli kaksi merkkisiin kertoimiin
        Integer multiplier; //valmis kerroin
        String repeat; //yksittainen toisto
        String substring = ""; //toistettava merkkijono
        while (index < end){ //main loop
            while (Character.isDigit(in.charAt(index))){ //luetaan kerroin
                part += in.charAt(index);
                index++;
            }
            while (Character.isLetter(in.charAt(index))){ //luetaan merkkijono
                substring = substring + in.charAt(index);
                index++;
                if (index == end){
                    break;
                }
            }
            multiplier = Integer.parseInt(part);
            repeat = new String(new char[multiplier]).replace("\0", substring); //toistetaan merkkijono kertoimen mukaan
            out += repeat;
            //for (int i = 0; i < multiplier; i++) {
                //out = out + substring;
            //}
            part = "";
            substring = "";
            }
        System.out.println(out); //tulostetaan tulos
    }
}

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: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of...

Test 7

Group: 2

Verdict: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of...

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of...

Test 15

Group: 3

Verdict: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of...