int trig=14;
int echo=27;
int led1=4;
int led2=2;
int led3=17; 
int distance;
void setup() {
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
pinMode(trig, OUTPUT);
pinMode(echo, INPUT);
pinMode(led1, OUTPUT);  //red
pinMode(led2, OUTPUT);  //green
pinMode(led3, OUTPUT);  //orange
}

void loop() {
  digitalWrite(trig, HIGH);
  Serial.println("signal went");
  delay(1000);
  digitalWrite(trig, LOW);
  distance=pulseIn(echo, HIGH);
  Serial.println("Signal received");
  int c = (distance*0.034/2);
  Serial.println(c);
  delay(1000);
  if(c>300) //red
  {
    digitalWrite(led1, HIGH);
    digitalWrite(led2, LOW);
    digitalWrite(led3, LOW);
  }
  else if(c>200)
    {
    digitalWrite(led1, LOW);
    digitalWrite(led2, HIGH);
    digitalWrite(led3, LOW);
  }
  else if(c<100)
   {
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(led3, HIGH);
  }
 
}