sensor pendeteksi banjir

#define trigPin 7
#define echoPin 6
#define ledaman 8
#define led1 9
#define led2 10
#define led3 11





void setup() {
 Serial.begin (505200);
 pinMode(trigPin, OUTPUT);
 pinMode(echoPin, INPUT);

 pinMode(ledaman, OUTPUT);
 pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
pinMode(led3, OUTPUT);

}

void loop() {
 long duration, distance;
 digitalWrite(trigPin, LOW);
 delayMicroseconds(2);
 digitalWrite(trigPin, HIGH);
 delayMicroseconds(10);
 digitalWrite(trigPin, LOW);
 duration = pulseIn(echoPin, HIGH);
 distance = (duration/2) / 29.1;

if(distance>=16) {
  digitalWrite(ledaman, HIGH);
  digitalWrite(led1, LOW);
  digitalWrite(led2, LOW);
  digitalWrite(led3, LOW);
}
else {
   digitalWrite(ledaman, LOW);
}
if(distance <= 15) {
 digitalWrite(led1, HIGH);
  digitalWrite(led2, LOW);
  digitalWrite(led3, LOW);
}

if(distance < 10) {
   digitalWrite(led2, HIGH);
  digitalWrite(led1, LOW);
  digitalWrite(led3, LOW);
}

if(distance < 5) {
  digitalWrite(led3, HIGH);
  digitalWrite(led2, LOW);
  digitalWrite(led1, LOW);
}

delay(500);
}