void setup() {
pinMode(switchPin01, INPUT);
pinMode(switchPin02, INPUT); // set the switch pin to be an input
pinMode(switchPin03, INPUT);
pinMode(greenLedPin, OUTPUT); // set the yellow LED pin to be an output
pinMode(redLedPin, OUTPUT);// set the red LED pin to be an output
}

void loop() {
// read the switch input:
switchState01 = digitalRead(switchPin01);
switchState02 = digitalRead(switchPin02);
switchState03 = digitalRead(switchPin03);

//enough light = 1, dark = 0 – then green
if (switchState01 == 1 && switchState02 == 0 && switchState03 == 1) {
// if the switch is closed:
digitalWrite(greenLedPin, HIGH); // turn on the yellow LED
digitalWrite(redLedPin, LOW); // turn off the red LED
}
else {
// if the switch is open:
digitalWrite(greenLedPin, LOW); // turn off the yellow LED
digitalWrite(redLedPin, HIGH); // turn on the red LED
}
}

// declare variables:
int switchPin01 = 1; //small photocell
int switchPin02 = 2; //large photocell
int yellowLedPin = 3;   //  digital output pin for an LED
int redLedPin = 4;      //  digital output pin for an LED
int switchState01 = 0;    // the state of the switch
int switchState02 = 0;    // the state of the switch

void setup() {
pinMode(switchPin01, INPUT);
pinMode(switchPin02, INPUT);  // set the switch pin to be an input
pinMode(yellowLedPin, OUTPUT);   // set the yellow LED pin to be an output
pinMode(redLedPin, OUTPUT);      // set the red LED pin to be an output
}

void loop() {
// read the switch input:
switchState01 = digitalRead(switchPin01);
switchState02 = digitalRead(switchPin02);

//covered (0), not(1) – then yellow
if (switchState01 == 0 && switchState02 == 0) {
// if the switch is closed:
digitalWrite(yellowLedPin, HIGH);    // turn on the yellow LED
digitalWrite(redLedPin, LOW);       // turn off the red LED
}
else {
// if the switch is open:
digitalWrite(yellowLedPin, LOW);   // turn off the yellow LED
digitalWrite(redLedPin, HIGH);     // turn on the red LED
}
}