use ++ operator

suppose a=6 and b=3

we can write c=a-(-b)
which will give us c=9

oh sorry I have considered as addition operator

use the variable u can get it

#include<Stdio.h>
#include<conio.h>

void main()
 {
   int a=10,b=20;
   while(b--) a++;
      printf("Sum is :%d",a);  
 }

#include <stdio.h>

int main ( int argc, char* argv [ ] )
{
	int value1 = 10;
	int value2 = 5;
	printf ( "\n The sum is :%d", value1 | value2 );
}

#include <stdio.h>

int add(int a,int b)
{
  if(!a)
     return b;
  else
     return add((a&b)<<1,a^b);
}

void main()
{
        int a=2, b=3, c;
        c = add(a,b);
        printf("%d\n",c);
}

#include<stdio.h>
int main()
{
 int a=3,b=5;
 while(a--)
 b = b++;
 
 printf("%d\n");

}

#include<stdio.h>

int main()
{
   int x=5,y=10;   //Use scanf otherwise
   int z=add(x,y);
   return 0;
}

int add(int a,int b)
{  
   int i;
   for(i=0;i<b;i++)
   {
     a++;
   }
   return a;
}

#include<stdio.h>
main()
{
 int a=5,b=6,s;
 int *p=a;
 s=&p[b];
 printf("%d",s);
}