public class DigitSum {

int sum = 0;

public static void main(String[] args) {

sumDigits(25);

}

private static int sumDigits(int number) {

if (number >= 100) {

int x2 = number % 100;

int y2 = (number - x2) / 100; //y2 is hundreds

if (x2 >= 10) {

int x = x2 % 10;

int y = (x2 - x) / 10; // y is tens

int x3 = number - (y2 * 100) - (y * 10); // x3 is ones

int total = y2 + y + x3;

System.out.println(total + " total");

return y;

}

} else if ((number < 100) && (number >= 10)) {

int x = number % 10;

int y = (number - x) / 10;

int x3 = number - (y * 10);

int total = y + x3;

System.out.println(total + " total");

return y;

} else if (number < 10) {

return -1;

}

return number;

}

}