int pot=A0;
int led=3;
int parlaklik;

void setup() {
  pinMode(pot, INPUT);
  pinMode(led, OUTPUT);
  // put your setup code here, to run once:

}

void loop() {
  parlaklik=analogRead(pot);
  parlaklik=map(parlaklik, 0, 1023, 0, 255);
  analogWrite(led, parlaklik);
  // put your main code here, to run repeatedly:

}