Goshh, need some help over here!

Question

hi everyne.
need help.
U insert a number e.g ( -12 ) the operation will be: (-1) + 2 = 1
e.g : - 42 = (-4) + 2 = -2
I cannot find a way to do that.
here is the code for simple sum:
int sum = 0;
          int aux;
          int digit = 0;
          System.out.print("Insert  a number: ");
          int num = Teclado.intLido();
          aux = num;
          while(aux != 0 ) {
            digit = aux % 10;
            aux = aux / 10;
            if(digit > 0) {
                 sum += digit; when i say "digit > o " this digit is the second one, because the first is always positive.
So i need help to find a way to tell the computer if the second digit is negative it will deduct. e.g -12 -> (-1 ) + 2 = 1
Anyone could tell how to tell the computer if the second digit is negative or positive. I cannot find a way to tell that.
thanks!
Josh

Answer 1

what about num / 10 + Math.abs(num % 10) ?
:D
i know and with strings and length () to count the digits will be easier too.
But i can't use Math.abs etcc string length() etc.. just loops :P
Just wanna know how to tell the computer if the second digits (from right to left) is neg or pos. if neg (-12) (-1) +2 = 1 or (-41) = -4 +1 = -3
using this method with something else.
while(aux != 0 ) {
          digit = aux % 10;
          aux = aux / 10;
          if(digit > 0) {
               soma = soma + digito;
          }else if (digit < 0) {
// this line is wrong because i want it to see if the SECOND digit is < 0 and not the first which is always positive.
               sum = sum - digit;
Do u know what i mean?