Question

void main()
{
unsigned giveit=-1;
int gotit;
printf("%u ",++giveit);
printf("%u \n",gotit=--giveit);
}

why its output is 0 65535

Answer 1

Because you assign giveit to a -1 and then you add 1 to it which equals 0 and then you take gotit and assign it the value of giveit -1 which loops your unsigned data value back (like rolling an odometer on a car) so it now contains the "max" short in value of 65,535.