int led[8] = {19, 18, 5};
int curr1 = 0;
int prev1 = 0;
int curr2 = 0;
int prev2 = 0;
int curr3 = 0;
int prev3 = 0;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  for (int i = 0; i < 3; i++)
  {
    pinMode(led[i], OUTPUT);
  }
}

void loop() {
  // put your main code here, to run repeatedly:
  
  digitalWrite(led[0], HIGH);

  
    
    for (int i = 30; i > 0; )
    {
      curr1 = millis();
      if (curr1 - prev1 > 1000)
      {
        Serial.println("Go for " + String(i) + " seconds");
        prev1=curr1;
        i--;
      }
    }
    

  digitalWrite(led[0], LOW);

  
  digitalWrite(led[1], HIGH);
  for (int i = 5; i > 0; )
  {
    curr2=millis();
    
    while (curr2 - prev2 > 1000)
      {
        Serial.println("Observe for " + String(i) + " seconds");
        prev2=curr2;
        i--;
      }
  }

  digitalWrite(led[1], LOW);

  digitalWrite(led[2], HIGH);
  
  for (int i = 30; i > 0; )
  {
    curr3=millis();
    if(curr3-prev3 >1000)
    {
      Serial.println("Stop for " + String(i) + " seconds");
      prev3=curr3;
      i--;
    }
  }

  digitalWrite(led[2], LOW);

}