int bulbpin=13;
int btnpin=2;
void setup(){
  pinMode(bulbpin, OUTPUT);
  pinMode(btnpin, INPUT); 
 
}

void loop(){
   int btnvalue=digitalRead(btnpin);
  if(btnvalue==1){
    digitalWrite(bulbpin,HIGH);
  }
  else{
    digitalWrite(bulbpin,LOW);
  }
}