#define led 27
#define btn 14
#define Trig 15
#define Echo 2
#define buzzer 4
#define R 5
#define G 18
#define B 19
int distance=0,duration=0;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(led,OUTPUT);
  pinMode(Trig,OUTPUT);
  pinMode(Echo,INPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(btn, INPUT_PULLUP);
  pinMode(R, OUTPUT);
  pinMode(G, OUTPUT);
  pinMode(B, OUTPUT);
}
int ultrasonic()
{
  digitalWrite(Trig,LOW);
  delayMicroseconds(2);
  digitalWrite(Trig,HIGH);
  delayMicroseconds(10);
  digitalWrite(Trig,HIGH);
  duration=pulseIn(Echo,HIGH);
  distance=duration*0.034/2;
  return distance;
}

void loop() {
  Serial.println(ultrasonic());
  if((ultrasonic()<20) && (ultrasonic()>0))
  {
    digitalWrite(buzzer,HIGH);
  }  
  else{
    digitalWrite(buzzer,LOW);
  }
  if(digitalRead(btn))
  {
    digitalWrite(R,HIGH);
  }
  else{
    digitalWrite(R,LOW);
  }
  if((ultrasonic()>20) && (ultrasonic()<100))
  {
    digitalWrite(buzzer,HIGH);
  }  
  else{
    digitalWrite(buzzer,LOW);
  }
  if(digitalRead(btn))
  {
    digitalWrite(G,HIGH);
  }
  else{
    digitalWrite(G,LOW);
  }
  if(ultrasonic()>100)
  {
    digitalWrite(buzzer,HIGH);
  }  
  else{
    digitalWrite(buzzer,LOW);
  }
  if(digitalRead(btn))
  {
    digitalWrite(B,HIGH);
  }
  else{
    digitalWrite(B,LOW);
  }
}