binary shifting code example

Example: shifting on binary

a = 5 = 0000 0101
b = -10 = 1111 0110

a << 1 = 0000 1010 = 10
a << 2 = 0001 0100 = 20 

b << 1 = 0000 1010 = -20
b << 2 = 0001 0100 = -40