#include <Servo.h>

Servo servomotor;

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

void loop() {
  servomotor.write(0);
  delay(1500);

  servomotor.write(45);
  delay(1500);

  servomotor.write(90);
  delay(1500);

  servomotor.write(135);
  delay(1500);

  servomotor.write(180);
  delay(1500);
}

}