const int buttonPin = 3;
const int ledPin = 5;
int buttonState = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  pinMode(buttonPin, INPUT);
  buttonState = LOW;
}

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