int led = 13;
int pot = A0;
void setup() {
pinMode(led , OUTPUT);
}

void loop() {
int potValue = analogRead(pot);
int blinkSpeed = map(potValue , 0 , 1023 , 100 , 1000);

digitalWrite(led , HIGH);
  delay(blinkSpeed);
digitalWrite(led , LOW);
  delay(blinkSpeed);
}