Add and subtract two integers without using the + or - operators in java

Question

how can add two number without using + or - operators in java..

I have found one link for the same in c. http://prokutfaq.byethost15.com/AddTwoNumbersWithoutArithmetic

But, i am not able to implement in java. Please help me.

Answer 1

As Java has bitwise operators pretty similar to the ones used in the C source you reference I wonder why a simple translation of that code doesn't "just work".

Perhaps you should explain the point at which you get stuck.

Answer 2

Remember that Java by default has sign-extending shift operators (>>). There are unsigned variants available however (>>>).

Answer 3

I'm not sure you've looked at the link you gave. There is a really simple way to do it with recursion. Did you try to implement this one with Java ?

#include <stdio.h>
int add(int a, int b){
    if (!a) return b;
    else
      return add((a & b) << 1, a ^ b);
}

int main(){
    printf("Enter the two numbers: \n");
    int a,b;
    scanf("%d",&a);
    scanf("%d",&b);
    printf("Sum is: %d",add(a,b));
}

Answer 4

No matter if it is a homework or not, try this rather identical question handled earlier this week.

http://stackoverflow.com/questions/1149929/

Answer 5

(int)Math.log(Math.exp(a)*Math.Exp(b))

BigInteger.valueOf(a).add(BigInteget.valueOf(b)).intValue()

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