const int led [] = {19, 21, 22, 23};
const int pot = 13;


void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  for (int i = 0; i < 4; i++) {
    pinMode(led[i], OUTPUT);
  }
}

void loop() {
  int nilaipot = analogRead(pot);
  int nilaidelay = map(nilaipot, 0, 4095, 500, 50);

  for (int i = 0; i < 4; i++) {
    digitalWrite(led[i], HIGH);
    delay(nilaidelay);
    digitalWrite(led[i], LOW);
    delay(nilaidelay);
  }
}