Caneca smart programación

#include<Servo.h>
Servo servo;
int const trigPin = 6;
int const echoPin = 5;
void setup()
{
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
    servo.attach(3);
}
void loop()
{       int duration, distance;
digitalWrite(trigPin, HIGH);
delay(1);
digitalWrite(trigPin, LOW);
// Measure the pulse input in echo pin
duration = pulseIn(echoPin, HIGH);
// Distance is half the duration devided by 29.1 (from datasheet)
distance = (duration/2) / 29.1;
// if distance less than 0.5 meter and more than 0 (0 or less means over range)
if (distance <= 50 && distance >= 0) {
  servo.write(50);
    delay(3000);
} else {

  servo.write(160);
}
// Waiting 60 ms won't hurt any one
delay(60);
}