Pembelian barang dengan perulangan pilihan menu

Source code yang saya gunakan adalah sebagai berikut:

package tugas4;
/**
 *
 * @author Ridho-REX
 */
import java.util.Scanner;
public class Tugas4 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int menu, harga, jumlah, total=0, diskon, tagihan=0;
        System.out.println("    TOKO PAK ILYAS      ");
        do{
            System.out.println("        -Menu-          ");
            System.out.println("1. Sandwich krim kacang Rp. 15.000");
            System.out.println("2. Roti isi strawberry Rp. 10.000");
            System.out.println("3. Roti tawar gandum Rp. 8.000");
            System.out.println("4. Roti cream mocca Rp. 9.500");
            System.out.println("5. Roti kasur keju Rp. 8.000");
            System.out.println("\n -Masukkan Nomer Menu-  ");
            menu = input.nextInt();
            switch(menu){
                case 1: System.out.println(" -Sandwich krim kacang- ");
                        harga = 15000;
                        System.out.print("Masukkan jumlah pembelian ");
                        jumlah = input.nextInt();
                        total = harga*jumlah;
                        System.out.println("Sandwich Krim Kacang : "+total);
                        if(total>=100000){
                            diskon = (total*10)/100;
                            System.out.println("Anda mendapat diskon sebesar Rp. "+diskon);
                            total = total - diskon;
                        }
                        break;
                case 2: System.out.println(" -Roti isi strawberry- ");
                        harga = 10000;
                        System.out.print("Masukkan jumlah pembelian ");
                        jumlah = input.nextInt();
                        total = harga*jumlah;
                        System.out.println("Roti Isi Strawberry : "+total);
                        if(total>=150000){
                            diskon = (total*15)/100;
                            System.out.println("Anda mendapat diskon sebesar Rp. "+diskon);
                            total = total - diskon;
                        }
                        break;
                case 3: System.out.println(" -Roti tawar gandum- ");
                        harga = 8000;
                        System.out.print("Masukkan jumlah pembelian ");
                        jumlah = input.nextInt();
                        total = harga*jumlah;
                        System.out.println("Roti Tawar Gandum : "+total);
                        if(total>=100000){
                            diskon = (total*8)/100;
                            System.out.println("Anda mendapat diskon sebesar Rp. "+diskon);
                            total = total - diskon;
                        }
                        break;
                case 4: System.out.println(" -Roti cream mocca- ");
                        harga = 9500;
                        System.out.print("Masukkan jumlah pembelian ");
                        jumlah = input.nextInt();
                        total = harga*jumlah;
                        System.out.println("Roti Cream Mocca : "+total);
                        if(total>=90000){
                            diskon = (total*5)/100;
                            System.out.println("Anda mendapat diskon sebesar Rp. "+diskon);
                            total = total - diskon;
                        }
                        break;
                case 5: System.out.println(" -Roti kasur keju- ");
                        harga = 8000;
                        System.out.print("Masukkan jumlah pembelian ");
                        jumlah = input.nextInt();
                        total = harga*jumlah;
                        System.out.println("Roti Kasur Keju : "+total);
                        if(total>=100000){
                            diskon = (total*10)/100;
                            System.out.println("Anda mendapat diskon sebesar Rp. "+diskon);
                            total = total - diskon;
                        }
                        break;
            }
            tagihan = tagihan+total;
            System.out.println("\n1. Belum Selesai Membeli");
            System.out.println("0. Selesai membeli");
            menu = input.nextInt();
        }while(menu!=0);
        System.out.println("Total biaya yang harus dibayar dari semua barang Rp "+tagihan);
    }
}