const int trigPin = 4;
const int echoPin = 16;
const int ledPin = 33;
const int buzzerPin = 26;
 
void setup() {
  Serial.begin(115200);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
}
void loop() {
 
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
   int duration = pulseIn(echoPin, HIGH);
   int distance = duration*0.034 /2;
   Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  delay(10);
  if (distance < 200) {
    digitalWrite(ledPin, HIGH); 
    digitalWrite(buzzerPin, HIGH); 
  } else {
    digitalWrite(ledPin, LOW);  
    digitalWrite(buzzerPin, LOW);  
  }
}