// Forum: https://forum.arduino.cc/t/code-isnt-working-at-all/1226670/
// This Wokwi project: https://wokwi.com/projects/390348408867090433

const int trigpin = 8;
const int echopin = 7;

int red = 13;
int green = 12;

long duration;
int distance;

void setup()
{
  pinMode(trigpin, OUTPUT);
  pinMode(echopin, INPUT);
  pinMode(red, OUTPUT);
  pinMode(green, OUTPUT);
  Serial.begin(9600);
}

void loop()
{
  digitalWrite(trigpin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigpin, LOW);
  duration = pulseIn(echopin, HIGH);
  distance = duration * 0.034 / 2;
  Serial.println(distance);
  if (trigpin == HIGH) 
  {
    //void loop1();
    loop1();
  } 
  else 
  {
    //void loop1();
    loop1();
  }
}

void loop1() 
{
  if (distance > 40) 
  {
    digitalWrite(green, HIGH);
    digitalWrite(red, LOW);
  } 
  else if (distance <= 30) 
  {
    digitalWrite(green, LOW);
    digitalWrite(red, HIGH);
    delay(2000);
    digitalWrite(red, LOW);
    delay(2000);
    digitalWrite(red, HIGH);
  } 
  else if (distance <= 20) 
  {
    digitalWrite(green, LOW);
    digitalWrite(red, HIGH);
    delay(1000);
    digitalWrite(red, LOW);
    delay(1000);
    digitalWrite(red, HIGH);
  } 
  else if (distance <= 10) 
  {
    digitalWrite(green, LOW);
    digitalWrite(red, HIGH);
  }
}