int red = 4;
int green = 2;
int relay = 18;

int sensor = 34;


void setup() 
{
  pinMode(red, OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(relay, OUTPUT);
  pinMode(sensor, INPUT);
}

void loop() 
{
  int value = digitalRead(sensor);
  if(sensor==0)
  {
    digitalWrite(red,1);
    digitalWrite(green,0);
    digitalWrite(relay,1);
  }

  else if(sensor==1)
  {
    
    digitalWrite(red,0);
    digitalWrite(green,1);
    digitalWrite(relay,0);
  }

  delay(500);
}