#include <Servo.h>

Servo myservo;  // create servo object to control a servo

int pos = 0;    // variable to store the servo position
int buttonPin = 12; // declare button pin
int servoPin = 13; // declare the servo pin
int ledPin = 11; // declare led pin

void setup() {
  myservo.attach(13);  // attaches the servo on pin 13 to the servo object
}

void loop() {
    for (pos = 0; pos <= 180; pos += 1) { // servo from 0 degrees to 180 degrees in steps of 1 degree
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
    digitalWrite(ledPin, HIGH); // turn LED ON 
  }

delay(5000); // pause for some time at 180 degrees

  for (pos = 180; pos >= 0; pos -= 1) { // returns from 180 degrees to 0 degrees
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
    digitalWrite(ledPin, LOW); // turn LED OFF
  }
}