const int POT = A0;
const int LED1 = 9;

int sensorValue = 0;
int outputValue = 0;
void setup() {
  // put your setup code here, to run once:
 Serial.begin(9600);
 pinMode(LED1, OUTPUT);
 pinMode(POT, INPUT);
}

void loop() {
  // read pot value
  sensorValue = analogRead(POT);
  // map pot value to the brightness of the light
  outputValue = map(sensorValue, 0, 1023, 0, 255);
  // display results on serial monitor
  Serial.print("potvalue = ");
  Serial.print(sensorValue);
  Serial.print("\t ledbrightness = ");
  Serial.println(outputValue);

  // identify whether the value of output is 800 on pot
  if (sensorValue <= 800) {
  analogWrite(LED1, outputValue);
  } else {
  (sensorValue >= 801);
  analogWrite(LED1, LOW);
  }
}