void setup()
{
  pinMode(4, INPUT);
  pinMode(16,OUTPUT);
  Serial.begin(9600);
}

void loop()
{
  int motion= 0;
  motion = digitalRead(4);
  if(motion == HIGH)
  {
    digitalWrite(16, HIGH);
    Serial.println(motion);
    Serial.println("motion detected");
  }
  else
  {
    digitalWrite(16,LOW);
    Serial.println(motion);
    Serial.println("motion not detected");
}
delay(1000);
}