Swapping two integers without temporary variable.

We can do this thing in many ways, here are some.

int main()
{
        int x, y;
        printf("Enter x and y values \n");
        scanf("%d %d", &x, &y);
        printf("X=%d\t Y=%d\n", x, y);
        printf("AFTER SWAP \n");

        /* Swap using addition and subtraction */
        x = x+y;/*Limitation is there addition should */
        y = x-y;/* not over flow */
        x = x-y;
        printf("X=%d\t Y=%d\n", x, y);

        /* Swap using multiplication and division */
        x = x*y;/* Limitation is, Y should not be zero and*/
        y = x/y;/* and x*y should not overflow */
        x = x/y;
        printf("X=%d\t Y=%d\n", x, y);

        /* swap using exclusive OR */
        x = x^y;
        y = x^y;
        x = x^y;
        printf("X=%d\t Y=%d\n", x, y);

        return 0;
}

Give the one line code to tell the given number is power of '2' or not.

The "C" code snippet is here:

  int main()
  {
       int num;

      printf("Enter a number other than Zero \n");
      scanf("%d", &num);

      num&(num-1)?printf("Not a Power of 2 \n"):printf("Power of 2 \n"); 

      return 0;
  }