#define RED 3
#define BUTTON 2
int val;

void setup() {
  // put your setup code here, to run once:
  pinMode(RED, OUTPUT);
  pinMode(BUTTON, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  val=digitalRead(BUTTON);
  if(val==HIGH)
  {
    digitalWrite(RED, HIGH);
  }
  else
  {
    digitalWrite(RED, LOW);
  }
}