#include <Servo.h>

Servo myServo;

void setup() {
  myServo.attach(9);
  }

  void loop() {
    for (int pos = 0; pos <= 180; pos++) {
        myServo.write(pos);
            delay(15);
              }

                for (int pos = 180; pos >= 0; pos--) {
                    myServo.write(pos);
                        delay(15);
                          }
                          }