#include <Servo.h>
#define trigPin 6
#define echoPin 7
Servo servo;

int sound = 250;

void setup() {
Serial.begin (9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
servo.attach(5);
}

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 < 80) {
Serial.print(distance);
Serial.println(" cm");
servo.write(90);
}

else if (distance<180) {
Serial.print(distance);
Serial.println(" cm");
servo.write(180); }

else {
Serial.println("The distance is more than 180cm");
}
delay(500);
}