#include <Servo.h>
int buttonpin= 7;
int relaypin = 4;
int last_state= HIGH;

Servo myservo;  

long pos = 0;   

void setup(){
  Serial.begin(115200);
  pinMode(buttonpin, INPUT_PULLUP);
  pinMode(relaypin, OUTPUT);
}

void loop() {
  int value=digitalRead(buttonpin);
  if(last_state!=value){
    last_state=value;
    if(value==HIGH){
      digitalWrite(relaypin,LOW);
      Serial.println("released");
      for(pos=0;pos<=180;pos+=1){
        myservo.write(pos);
        delay(15);
      }
      for(pos=180;pos>=0;pos-=1){
        myservo.write(pos);
        delay(15);
      }
    }
    else{
        digitalWrite(relaypin,HIGH);
        Serial.println("pressed");
    }
  }
}