int pinLed1=15;
 int pinLed2=16;
 int pinLed3=17;
 int pinLed4=18;
 int pinPot=35;
 int valPot=0;
 float brillo=0;
 
void setup() {
  Serial.begin(115200);
  
  pinMode(pinLed1, OUTPUT);
  pinMode(pinLed2, OUTPUT);
  pinMode(pinLed3, OUTPUT);
  pinMode(pinLed4, OUTPUT);
  pinMode(pinPot, INPUT);
}

void loop() {
  
 valPot= analogRead(pinPot);
 brillo= (valPot*255/4095);
 Serial.println(brillo);

if(brillo<100)
{
for (int i = 15; i <= 16; i++) {
   Serial.println(i);
   digitalWrite(pinLed1, HIGH);
   digitalWrite(pinLed2, HIGH);
   delay(500);
   digitalWrite(pinLed1, LOW);
   digitalWrite(pinLed2, LOW);
   delay(500);
   }
   } else  { 
   for (int i = 18; i >= 17; i--) { 
    Serial.println(i);
    digitalWrite(pinLed3, HIGH);
    digitalWrite(pinLed4, HIGH); 
    delay(500); 
    digitalWrite(pinLed3, LOW); 
    digitalWrite(pinLed4, LOW); 
    delay(500);
    }
   }
      }