const int redLED = 6;
const int greenLED = 7;
const int buzzer = 8;

void setup() {
  pinMode(redLED, OUTPUT); 
  pinMode(greenLED, OUTPUT);
  pinMode(buzzer, OUTPUT);  
}

void loop() {
  digitalWrite(redLED, HIGH);  
  digitalWrite(greenLED, LOW); 
  tone(buzzer, 1000);          
  delay(300);                  

  digitalWrite(redLED, LOW);   
  digitalWrite(greenLED, HIGH); 
  tone(buzzer, 500);          
  delay(300);                  

  digitalWrite(redLED, HIGH);  
  digitalWrite(greenLED, LOW); 
  tone(buzzer, 1200);          
  delay(200);                  

  digitalWrite(redLED, LOW);  
  digitalWrite(greenLED, HIGH); 
  tone(buzzer, 400);          
  delay(200);                  
}