int trigger=4;
int echo=5;
int r = 25;
int o = 33;
int g = 32;
int buzzer = 26;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(r, OUTPUT);
  pinMode(o, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(trigger, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(buzzer, OUTPUT);
}

int finding_distance(){
  digitalWrite(trigger, HIGH);
  delay(100);
  digitalWrite(trigger, LOW);
  float a=pulseIn(echo, HIGH);
  return(a*0.034/2);
}
void loop() {
   noTone(buzzer);
  int distance=finding_distance();
  Serial.print(distance);
  Serial.println(" cm");

  if(distance>300){
    digitalWrite(g, HIGH);
    digitalWrite(o, LOW);
    digitalWrite(r, LOW);

    Serial.println("You are safe");
  }
  else if(distance>200&&distance<=300){
    digitalWrite(o, HIGH);
    digitalWrite(r, LOW);
    digitalWrite(g, LOW);
    Serial.println("You are unsafe");
  }
  else{
    digitalWrite(r, HIGH);
    digitalWrite(o, LOW);
    digitalWrite(g, LOW);
    tone(buzzer, 999, 1000);
    Serial.println("You are in Danger");
  }
  delay(1000); // this speeds up the simulation
}