sum (adding 2 numbers ) without plus operator

Question

Can anyone explain the logic how to add a and b?

#include 

int main()
{
     int a=30000, b=20, sum;
     char *p;
             


        

Answer 1

An alternative to the pointer arithmetic is to use bitops:

#include 
#include 

unsigned addtwo(unsigned one, unsigned two);

unsigned addtwo(unsigned one, unsigned two)
{
unsigned carry;

for( ;two; two = carry << 1)    { 
        carry = one & two; 
        one ^= two;
        } 
return one;
}

int main(int argc, char **argv)
{
unsigned one, two, result;

if ( sscanf(argv[1], "%u", &one ) < 1) return 0;
if ( sscanf(argv[2], "%u", &two ) < 1) return 0;

result = addtwo(one, two);

fprintf(stdout, "One:=%u Two=%u Result=%u\n", one, two, result );

return 0;
}