//write a program to control an led with respeat the positon of switch.led is connect 
//to gpio2 and switch gpio4
//use extranal register for swtich
void setup() {
  pinMode(4,INPUT_PULLDOWN);
  pinMode(2,OUTPUT);
 
}

void loop() {
  int x=digitalRead(4);
  if(x==HIGH){
    digitalWrite(2,HIGH);
  }
  else{
    digitalWrite(2,LOW);
  }
  

}