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
        char ch;
        while (index < end){ //main loop
            ch = in.charAt(index);
            while (ch >= '0' && ch <= '9'){ //luetaan kerroin
                part = part + ch;
                index++;
                ch = in.charAt(index);
            }
            ch = in.charAt(index);
            while (ch >= 'A' && ch <= 'Z'){ //luetaan merkkijono
                substring = substring + ch;
                index = index + 1;
                if (index == end){
                    break;
                }
                ch = in.charAt(index);
            }
            multiplier = Integer.parseInt(part);
            repeat = new String(new char[multiplier]).replace("\0", substring); //toistetaan merkkijono kertoimen mukaan
            out = out + repeat;
            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 range: 1001
	at java.lang.String.charAt(String.java:658)
	at Pakkaus.main(Pakkaus.java:34)

Test 7

Group: 2

Verdict: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 2000
	at java.lang.String.charAt(String.java:658)
	at Pakkaus.main(Pakkaus.java:34)

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 range: 3483
	at java.lang.String.charAt(String.java:658)
	at Pakkaus.main(Pakkaus.java:34)

Test 15

Group: 3

Verdict: RUNTIME ERROR

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 6100
	at java.lang.String.charAt(String.java:658)
	at Pakkaus.main(Pakkaus.java:34)