Gray Code Encoder
The reflected binary code (RBC), also known as Gray code, is an ordering of the binary numeral system such that two successive values differ in only one bit (binary digit).
For example, the representation of the decimal value 1 in binary would normally be 001 and 2 would be 010. In Gray code, these values are represented as 001 and 011. That way, incrementing a value from 1 to 2 requires only one bit to change, instead of two.
For each numeric argument in decimal form, print the same number in reflected binary (Gray code) form.
The numbers range from 0 to 4095 inclusive.