int pot;
int led;
void setup() {
  // put your setup code here, to run once:
  pinMode(A0, INPUT);
  pinMode(9, OUTPUT);
  
  }
 void loop() {
    pot= analogRead(A0);            // Read potentiometer (0–1023)
    led= map(pot, 0, 1023, 0, 255); // Scale to 0–255
    analogWrite(9, led);       // Set LED brightness
  }