The value of E1 << E2 is E1 left-shifted E2 bit positions; vacated bits are
zero-filled.
If E1 has an unsigned type, the value of the result
is , reduced modulo
one more than the maximum value representable in the result type.
Otherwise, if
E1 has a signed type and non-negative value, and is
representable in the corresponding unsigned type of the result type, then
that value, converted to the result type, is the resulting value; otherwise, the
behavior is undefined.