#include <Servo.h>
Servo myservo;  

void setup() {
  myservo.attach(9);  
  Serial.begin(9600); 
}

void loop() {
  for (int angle = 0; angle <= 180; angle++) {
    myservo.write(angle);
    Serial.println(angle); 
    delay(15); 
  }
  
  for (int angle = 180; angle >= 0; angle--) {
    myservo.write(angle);
    Serial.println(angle);  
    delay(15);
  }
}