US+LDR

#define echoPin 2
#define trigPin 3
#define ledPin 13
#define ldrPin A0

long duration;
int distance;

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(ldrPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  US();
  LDR();
}

void US() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
}

void LDR() {
  int ldrStatus = analogRead(ldrPin);
  Serial.print(ldrStatus);
  if (ldrStatus <= 200) {
    digitalWrite(ledPin, HIGH);
    Serial.println("Its DARK, Turn ON the LED");
  }
  else {
    digitalWrite(ledPin, LOW);
    Serial.println("Its BRIGHT, Turn OFF the LED");
  }
}