int trigger=19;
int echo=18;
int light1=12;
int light2=27;
int light3=14;
int buzzer=13;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(trigger, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(light1, OUTPUT);
  pinMode(light2, OUTPUT);
  pinMode(light3, OUTPUT);
  pinMode(buzzer, OUTPUT);
}

int Ultra_sonic(){
  digitalWrite(trigger, HIGH);
  delay(100);
  digitalWrite(trigger, LOW);
 float recieved= pulseIn(echo, HIGH);
 float converted=(recieved*0.034/2)+1;
 return(converted);

}

void loop() {
  // put your main code here, to run repeatedly:
  int actual_distance=Ultra_sonic();
  Serial.println(actual_distance);
  delay(1000);
if(actual_distance>300){
    digitalWrite(light3, HIGH);
    digitalWrite(light2, LOW);
    digitalWrite(light1, LOW);
    Serial.println("you are safe");
    noTone(buzzer);
}
if(actual_distance>=200&&actual_distance<=300){
  digitalWrite(light2, HIGH);
  digitalWrite(light3, LOW);
  digitalWrite(light1, LOW);
  Serial.println("be in consious");
  noTone(buzzer);
}
if(actual_distance<200){
  digitalWrite(light3, LOW);
  digitalWrite(light2, LOW);
  digitalWrite(light1, HIGH);
  tone(buzzer,5000);
  Serial.println("you are in danger");
}
}