Thread: Returning wrong value without modifying!!

Iam trying to solve a question.The question is

Finding sum of digits of a number until sum becomes single digit.

.
Example
Input : 12345
Output: 6

The individual digits should be added untill it become single digit.1+2+3+4+5=15 -->1+5=6.

In the below code the input is:
i)first line number of test cases
ii)second line is the number.

When I run the code , the following are the inputs Iam giving:
1;
12345;
The output should be "6" but it is printing "15".It is not printing "6".Iam unable to understand what's wrong woth the below code.Plz. help!!

import java.util.Scanner;
class AddNum{
 
	public int  Add(int num) {
		int x;
		int sum=0;
		int rem;
 		while(num>0) {
 
			rem=num%10;
			sum=sum+rem;
			num/=10;
		}
		if(sum>9) {
			Add(sum);
		}
		return sum;
 
 
	}	
}
 class IndividSum {
 
public static void main(String[]  args)throws Exception{
	Scanner sc=new Scanner(System.in);
	int test=sc.nextInt();
	AddNum obj=new AddNum();
	int num[]=new int[test];
	int Ans[]=new int[test];
	for(int i=0;i<test;i++) {
		num[i]=sc.nextInt();
	}
	for(int i=0;i<test;i++) {
		Ans[i]= obj.Add(num[i]);
		System.out.println(Ans[i]);
 
	}
sc.close();
}
 
}

Actually the sum value in class AddNum is 6 but when the value is returned to Ans[i] in class IndividSum,it is showing 15.My question is why is it returning wrong value?

the problem is in your recursion, when it backs out sum is the old value, you need to change your recursive call to:

if(sum>9) {
	sum = Add(sum);
}