#include<Servo.h>//libary Servo
Servo myservo;
void setup() {
  Serial.begin(9600);
  myservo.attach(3);
  // put your setup code here, to run once:
  
}

void loop() {
  myservo.write(45);
  delay(500);
  myservo.write(90);
  delay(500);
  myservo.write(135);
  delay(500);
  myservo.write(180);
  delay(500);
  // put your main code here, to run repeatedly:

}