los pines estan declarados aca
int boton = A5;
int estadoBoton;
int rele1 = 2;
int rele2 = 3;
int rele3 = 4;
int rele4 = 5;
int rele5 = 6;
int rele6 = 7;
int rele7 = 8;
int rele8 = 9;
int rele9 = 10;
int rele10 = 11;
int rele11 = 12;
int rele12 = 13;
int rele13 = 14;
int rele14 = 15;
int rele15 = 16;
int rele16 = 17;
después los declaro en el setup como el nombre "rele1"
(rele 1 es el pin 2)
pinMode(rele1, INPUT);