int pir = 8;
int relay = 12;
int state = LOW;
int value = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(relay, OUTPUT);
  pinMode(pir, INPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  value = digitalRead(pir);

  if(value == HIGH){
    digitalWrite(relay,HIGH);
    
    if(state == LOW){
      Serial.print("Motion detected!\n");
      state = HIGH;
    }
  }

  else{
    digitalWrite(relay,LOW);

    if(state == HIGH){
    Serial.print("Motion ended!\n");
    state = LOW;
    }
  }
}