// Define the buzzer pin
const int buzzerPin = 8;
const int myDelay = 150;
//const duration = 100;

void setup() {
  // Set the buzzer pin as an OUTPUT
  pinMode(buzzerPin, OUTPUT);
}

void loop() {
  // Make the buzzer beep
  beep();

  // Wait for 5 seconds
  delay(1000);
}

void beep() {
  int melody[] = {400,400,800,1000,1500,2500,3000,3500,4000,4500,4750};// 11 elements
  for(int i = 0; i<=11; ++i){
    tone(buzzerPin, melody[i], 100);//min 100 
    delay(myDelay);
  }
  noTone(buzzerPin);
}