Study of bitwise operators.
  #include <stdio.h>

int main(void)
{
unsigned int n = 2;

printf( "\nn = %u", n );
printf( "\nn << 2 = %u", n << 2 );
printf( "\nn >> 2 = %u", n >> 2 );
printf( "\nn & 3 = %u", n & 3 );
printf( "\nn | 3 = %u", n | 3 );
printf( "\nn ^ 3 = %u", n ^ 3 );
printf( "\n~n = %u", ~n );

return 0;
}