int potpin = A0;
int LED = 11;
int val;
int brightness;
void setup() {
  // put your setup code here, to run once:
  
  pinMode(LED, OUTPUT);

}

void loop() {
  // put your main code here, to run repeatedly:
  val = analogRead(potpin);  
  brightness = map(val, 0, 1023, 0, 255);         
  analogWrite(LED, brightness); 
}