### Java program to find the sum of all digits of a number :

In this tutorial, we will learn how to find the sum of all digits of a number in Java. Algorithm we are using is as below :

### Algorithm :

- Start one
*infinite*loop. This loop will run infinite times till user insert*‘-1’*as input. - Take the number from the user as input.
- Declare one variable as
*‘0’*to store the sum. - Using one ’
*while*’ loop, get the*modulo 10*of the number and add it to the sum. If the number is*123*, get*‘123%10’ i.e. 3*and add it to sum. - Now, divide the number
*by 10*and set it as new value. i.e. for*123, set it to 123/10 = 12* - Do this till the number become_ ‘0’._
- Finally, Print out the result.

### Example program :

```
import java.util.Scanner;
public class Main {
private static void println(String message) {
System.out.println(message);
}
public static void main(String[] args) throws java.lang.Exception {
Scanner sc = new Scanner(System.in);
while (true) {
println("");
println("Enter a number ( -1 to exit ): ");
int no = sc.nextInt();
if (no == -1) {
break;
}
int sum = 0;
while (no > 0) {
sum += no % 10;
no = no / 10;
}
println("Sum of all numbers is " + sum);
}
}
}
```

### Example Output:

```
Enter a number ( -1 to exit ):
1
Sum of all numbers is 1
Enter a number ( -1 to exit ):
12
Sum of all numbers is 3
Enter a number ( -1 to exit ):
123
Sum of all numbers is 6
Enter a number ( -1 to exit ):
1234
Sum of all numbers is 10
Enter a number ( -1 to exit ):
12345
Sum of all numbers is 15
Enter a number ( -1 to exit ):
123456
Sum of all numbers is 21
Enter a number ( -1 to exit ):
-1
Process finished with exit code 0
```

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