#define pot A0
#define red 2
#define green 3
#define blue 4
int analog = 0 ;
float volt = 0 ;
int last_value = 0 ;

void setup() {
  pinMode(pot, INPUT);
  pinMode(red, OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(blue, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  analog = analogRead(pot);
  if(analog<100){
    digitalWrite(red, LOW);
    digitalWrite(green, LOW);
    digitalWrite(blue, LOW);
  }
  else if(analog <340){
    digitalWrite(red, HIGH);
    digitalWrite(green, LOW);
    digitalWrite(blue, LOW);
  }
  else if(analog <680){
    digitalWrite(red, HIGH);
    digitalWrite(green, HIGH);
    digitalWrite(blue, LOW);
  }
  else if(analog >680){
    digitalWrite(red, HIGH);
    digitalWrite(green, HIGH);
    digitalWrite(blue, HIGH);
  }
  if(last_value != analog ){
    last_value = analog ;
    volt = (5.0*analog)/1023.0; 
    Serial.print("Value = ");
    Serial.println(analog);
    Serial.print("Volt = ");
    Serial.println(volt);
    delay(1000);
  }
}