#include <Servo.h>
#define BUTTON_PIN 4

Servo myservo;

int pos = 0;

void setup() {
  // put your setup code here, to run once:
  myservo.attach(3);
  Serial.begin(115200);
  pinMode(BUTTON_PIN, INPUT_PULLUP);

}

int lastState = HIGH;
void loop() {
  // put your main code here, to run repeatedly:
  int value = digitalRead((BUTTON_PIN));
  if (lastState != value) {
    lastState = value;
    if (value == HIGH) {
      Serial.println(" released");
    }
  
  for (pos = 180; pos >= 90; pos -= 1) {
    myservo.write(pos);
    delay(5);
  }

      for (pos = 90; pos <=180; pos += 1) {
    myservo.write(pos);
    delay(5);
  }

  }
}