## Friday, 19 August 2016

### Chapter 6 Exercise 2, Introduction to Java Programming, Tenth Edition Y. Daniel LiangY.

*6.2 (Sum the digits in an integer) Write a method that computes the sum of the digits in an integer. Use the following method header: public static int sumDigits(long n) For example, sumDigits(234) returns 9 (2 + 3 + 4). (Hint: Use the % opera- tor to extract digits, and the / operator to remove the extracted digit. For instance, to extract 4 from 234, use 234 % 10 (= 4). To remove 4 from 234, use 234 / 10 (= 23). Use a loop to repeatedly extract and remove the digit until all the digits are extracted. Write a test program that prompts the user to enter an integer and displays the sum of all its digits.

import java.util.Scanner;

public class ProgrammingExercise6_2 {

public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter an integer:");
long n = input.nextLong();

System.out.println("The sum is " + sumDigits(n));
}

public static int sumDigits(long n) {

int sum = 0;
do {
sum += n % 10;

} while ((n = n / 10) != 0);

return sum;

}
}


#### 1 comment :

1. Hello! can anyone simplify what was happening in do while loop?