ModAdd

import java.util.Scanner;

public class ModAdd {

	    public static void main(String[] args) {
	        Scanner scan = new Scanner(System.in);
//	        String a = "93";
//	        String b = "17";
	        System.out.println(modAdd(scan.nextLine(), scan.nextLine()));
//	        System.out.println(modAdd(a,b));

	        scan.close();
	        
	    }
	    
	    public static String modAdd(String numberOne, String numberTwo) {
	        StringBuilder stringBuilder = new StringBuilder();
	        int diffLength = numberOne.length() - numberTwo.length();
	        if(diffLength > 0) {
	        	stringBuilder.append(numberOne.substring(0, diffLength));
	        	for(int i = 0; i < numberTwo.length(); i++) {
	        		stringBuilder.append((numberOne.charAt(diffLength + i) + numberTwo.charAt(i) - 96) % 10);
	        	}
	        	
	        	
	        }
	        else if(diffLength < 0) {
	        	diffLength = -diffLength;
	        	stringBuilder.append(numberTwo.substring(0, diffLength));
	        	for(int i = 0; i < numberOne.length(); i++) {
	        		stringBuilder.append((numberOne.charAt(i) + numberTwo.charAt(diffLength + i) - 96) % 10);
	        	}
	        }
	        else {
	        	for(int i = 0; i < numberOne.length(); i++) {
	        		stringBuilder.append((numberOne.charAt(i) + numberTwo.charAt(i) - 96) % 10);
	        	}
	        }
	        
	        return stringBuilder.toString().replaceFirst("^0+(?!$)", "");
	    }
	  
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED