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(4, OUTPUT);   //red
pinMode(17, OUTPUT); //green
pinMode(2, 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>=100)  //red
  {
    digitalWrite(4, HIGH);
    delay(100);
  }
  else
  {
    digitalWrite(4, LOW);
    delay(10);
  }
}