int trigger=4;
int echo=5;
int red=17;
int green=18;
int orange=2;

void setup() {
  
  Serial.begin(115200);
  pinMode(trigger, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(red,OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(orange, OUTPUT);
}

int finding_distance(){
  digitalWrite(trigger, HIGH);
  delay(100);
  digitalWrite(trigger, LOW);
  float a=pulseIn(echo, HIGH);
  return(a*0.034/2);
}
void loop() {
  int distance=finding_distance();
  Serial.println(distance);
  if (distance>=300){
  digitalWrite(green, HIGH);
  digitalWrite(red, LOW);
  digitalWrite(orange, LOW);
  Serial.print("you are in safe zone");
  }
  else if (300>distance && distance>=200)
  {
    digitalWrite(orange, HIGH);
    digitalWrite(red, LOW);
    digitalWrite(green, LOW);
    Serial.println("you are in unsafe zone");
  }
  else{
    digitalWrite(red, HIGH);
    digitalWrite(green, LOW);
    digitalWrite(orange, LOW);
    Serial.println("you are in danger zone");
  }

}