#include<Servo.h>

Servo myservo;

int pos=0;
 
void setup() {
  // put your setup code here, to run once:
  myservo.attach(9);
}

void loop() {

  for(pos=0; pos<=180; pos+=1){
    myservo.write(pos);
    delay(56);
  }
   for(pos=180; pos>=0; pos-=1){
    myservo.write(pos);
    delay(56);
  }
  // put your main code here, to run repeatedly:

}