tugas pbo

pbo

import java.util.Scanner;
public class jumlah{
  public static void main (String[] args) {
	 	Scanner scan = new Scanner(System.in);
	 	
	 	String bil1 = new String("");
	 	System.out.println ("bilangan 1 :");
	 	//bil1 = scan.next();
	 	if (scan.hasNextInt()){
	 		bil1 = scan.next();
	 	}else{
	 		System.out.println ("invalid integer");
	 		return;
	 	}
	 	String bil2 = new String("");
	 	
	 	System.out.println ("bilangan 2 :");
	 	//bil2 = scan.next();
	 	
	 	if (scan.hasNextInt()){
	 		bil2 = scan.next();
	 	}else{
	 		System.out.println ("invalid integer");
	 		return;
	 	}
	 	
	 	int max_len;
	 	if(bil1.length() > bil2.length()){
	 		max_len = bil1.length();
	 	}else{
	 		max_len = bil2.length();
	 	}
	 	 	
	 	String[] arr_bil1 = new String[bil1.length()];
	 	for(int x = 0; x < bil1.length(); x = x+1) {
	 		String a = String.valueOf(bil1.charAt(bil1.length() - x - 1));
	 		arr_bil1[x] = a;
	 	}
	 	
	 	String[] arr_bil2 = new String[bil2.length()];
	 	for(int x = 0; x < bil2.length(); x = x+1) {
	 		String a = String.valueOf(bil2.charAt(bil2.length() - x - 1));
	 		arr_bil2[x] = a;
	 	}
	 	
	 	
	 	Integer a;
	 	Integer b;
	 	
	 	Integer simpan = 0;
	 	Integer sum = 0;
	 	String hasil = new String("");
	 	for(int x = 0; x < max_len; x = x+1) {

	 		if(x < bil1.length()){
	 			a = Integer.parseInt(arr_bil1[x]);
	 		}else{
	 			a = 0;
	 		}
	 		
	 		if(x < bil2.length()){
	 			b = Integer.parseInt(arr_bil2[x]);
	 		}else{
	 			b = 0;
	 		}
	 		
	 		sum = a + b + simpan;
	 		
	 		if(sum >= 10){
	 			simpan = sum / 10;
	 			sum = sum - 10;
	 		}else{
	 			simpan = 0;
	 		}
	 		hasil =  String.valueOf(sum) + hasil;
	 		
	 	}
	 	
	 	if(simpan > 0){
	 		hasil =  String.valueOf(simpan) + hasil;
	 	}
	 		
	 	
	 	System.out.println ("hasilnya : " + hasil);

	}
}