Java program to compute the sum of digits in a given numbers

In this tutorial, we will discuss a concept of Java program to compute the sum of digits in a given numbers

In the Java programming language, we can use for loop ,while loop and do-while loop to compute the sum of digits in a given numbers

In this article, we are going to learn how to find the sum of digits in a given numbers

program to find the sum of digits

Calculate the sum of digits using the for loop

Program 1

import java.util.Scanner;
class SumOfDigits1{
public static void main(String args[]){
    long count,sum=0,digits;
    Scanner scan=new Scanner(System.in);
//create a scanner object for input

//get input from the user for rows
System.out.print("Enter the number for sum: ");
long num=scan.nextInt();
 
count=num;
for(count=num; num>0; num/=10)
{
    digits=num%10;
    sum=sum+digits;
    
}

System.out.print("Given number is: "  + count);
System.out.print("\nSum of the digits: "  + sum);
}
}

When the above code is executed, it produces the following results

Case 1

Enter the number for sum:1100
Given number is: 1100
Sum of the digits:2

Case 2

Enter the number for sum:3456
Given number is: 3456
Sum of the digits:18

Calculate the sum of digits using the while loop

Program 2

import java.util.Scanner;
class SumOfDigits{
public static void main(String args[]){
    long count,sum=0,digits;
    Scanner scan=new Scanner(System.in);
//create a scanner object for input

//get input from the user for rows
System.out.print("Enter the number for num: ");
long num=scan.nextInt();
 count=num;

while(num>0)
{
    digits=num%10;
    sum=sum+digits;
    num/=10;
    
}

System.out.print("Given number is: "  + count);
System.out.print("\nSum of the digits: "  + sum);
}
}

When the above code is executed, it produces the following results

case 1

Enter the number:1200
Given number is: 1200
Sum of the digits:3

case 2

Enter the number:1468
Given number is: 1468
Sum of the digits:19

Calculate the sum of digits using the do-while loop

Program 3

import java.util.Scanner;
class SumOfDigits2{
public static void main(String args[]){
    long count,sum=0,digits;
    Scanner scan=new Scanner(System.in);
//create a scanner object for input

//get input from the user for rows
System.out.print("Enter the number for num: ");
long num=scan.nextInt();
 count=num;
do{
    digits=num%10;
    sum=sum+digits;
    num/=10;
    
}
while(num>0);


System.out.print("Given number is: "  + count);
System.out.print("\nSum of the digits: "  + sum);
}
}

When the above code is executed, it produces the following results

case 1

Enter the number for num: 1111
Given number is:1111
Sum of the digits:4

case 2

Enter the number for num: 9876
Given number is:9876
Sum of the digits:30

Methods

Declare the variable num,count and digits as long type.
Declare and initialize variable sum to Zero.
Receive input from the user for the value to store the variable num and to find the sum of digits.
Using a loop (for loop , while loop, do-while loop) get each digit of the number and add it to the to a variable to find the sum.
Display the sum of the digits of the number.