Delta_G:
What you have to understand is that D1, D2 etc are symbols standing for numbers. For each there is a number you could use. This is perfectly valid.for(int pin = D1; pin < D3; pin++){
That assumes that they are consecutive.
Delta_G:
What you have to understand is that D1, D2 etc are symbols standing for numbers. For each there is a number you could use. This is perfectly valid.for(int pin = D1; pin < D3; pin++){
That assumes that they are consecutive.