int led = 3;
int buton = 4;
int ldr_deger;

void setup() {
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  pinMode(buton, INPUT);
}

void loop() {
  if (digitalRead(buton) == HIGH) {
    ldr_deger = analogRead(A4);
    Serial.print("Ölçülen ışık seviyesi ");
    Serial.print(ldr_deger);
    Serial.print(", LED ");
    Serial.print(ldr_deger / 4);
    Serial.println(" ms aralıklar ile yanıp sönmektedir.");}
  if (ldr_deger!=0){ 	
    digitalWrite(led, HIGH);
    delay(ldr_deger / 4);
    digitalWrite(led, LOW);
    delay(ldr_deger / 4);}
}