Hello ..
I have a few questions about. the Modulo operation
0%2 = ????
1%2 = ????
3%2= ????
Thanks for the help
What gets printed on the serial monitor when you tried? 
[u]Modulo[/u] or modulus is the remainder after (integer) division.
X = 5 % 4 ; // X is 1
X = 6 % 4 ; // X is 2
X = 8 % 4 ; // X is 0