void setup() {
  pinMode(13, OUTPUT);
  pinMode(8, INPUT);
  Serial.begin(9600);
}

void loop() {
int x = digitalRead(8);
if(x==1){
  digitalWrite(13,HIGH);
  Serial.println("Switch is on");
}
else if(x==0) {
  digitalWrite(13,LOW);
  Serial.println("Switch is off");
}  

}