// constants won't change. 
// set pin numbers:
const int buttonPin = 0;     // the number of the pushbutton pin
const int redPin =  2;      // the number of the LED pin
const int greenPin = 3;      // the number of the LED pin
const int bluePin = 4;      // the number of the LED pin

// initialize variables:
int buttonState = 0;         // variable for reading the pushbutton status

void setup() {

  
  
  // initialize input/OUTPUT:
  pinMode(buttonPin, INPUT); 
  pinMode(redPin, OUTPUT); 
  pinMode(greenPin, OUTPUT); 
  pinMode(bluePin, OUTPUT);   
}

void loop(){
  // read the state of the pin the pushbutton is connected to:
  buttonState = digitalRead(buttonPin);

  // is the push button pressed?
  // if not pressed - the button state is HIGH 
  // the pull up resistor the button / pin 3 makes the button state HIGH by default.
  if (buttonState == 1) {     
    // turn LED off (LED is off by default) 
    digitalWrite(redPin, 255); 
    digitalWrite(greenPin, 255); 
    digitalWrite(bluePin, 255);
  } 
  //otherwise.....
  // button is pressed
  else {
    // turn LED on:
    digitalWrite(redPin, 255); 
    digitalWrite(greenPin, 255); 
    digitalWrite(bluePin, 0); 
  }
}