swap

void swapSigned(int *a, int *b)
{
    /** 1st method: sum and subtraction swap
    * Beware of overflow if using high values.
    */

    *a=*a+*b;
    *b=*a-*b;
    *a=*a-*b;
}

void swap(int *a, int *b)
{
    /** 2nd method: boolean swap
    * It completely avoids overflow.
    */

    *a=(*a)&(*b);
    *b=(*a)&(*b);
    *a=(*a)&(*b);
}