#define relay 2
#define button 4

void setup() {
  pinMode(relay, OUTPUT);
  pinMode(button, INPUT);
  Serial.begin(9600);
}

void loop() {
  int tekan = digitalRead(button);
  delay(300);
  if (tekan == 1) {
    digitalWrite(relay, 1);
  } else {
    digitalWrite(relay, 0);
  }
  Serial.println(tekan);
}