include <Servo.h>

Servo myservo;

int pos = 0;

void setup() {
  // put your setup code here, to run once:
  myservo.attach(22);
}

void loop() {
  // put your main code here, to run repeatedly:
  for(pos = 0 ; pos <= 180 ; pos += 1){
    myservo.write(pos);
    delay(15);
  }
  for(pos = 180 ; pos >= 0 ; pos -= 1){
    myservo.write(pos);
    delay(15);
  }
}