Project 2 - Measuring the distance of an object using ultrasonic sensor and also smoothen the sensor data using moving average filter

Code:

int trigPin = 11; // Trigger
int echoPin = 12; // Echo
long duration, cm, inches;
long sum=0;
long avg;
int i;

void setup()

{
        //Serial Port begin
        Serial.begin (9600);
        //Define inputs and outputs
        pinMode(trigPin, OUTPUT);
        pinMode(echoPin, INPUT);
}

void loop()

{
        // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
        // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
        digitalWrite(trigPin, LOW);
        delayMicroseconds(5);
        digitalWrite(trigPin, HIGH);
        delayMicroseconds(10);
        digitalWrite(trigPin, LOW);

       // Read the signal from the sensor: a HIGH pulse whose
       // duration is the time (in microseconds) from the sending
      // of the ping to the reception of its echo off of an object.
        pinMode(echoPin, INPUT);
        duration = pulseIn(echoPin, HIGH);

     // Convert the time into a distance

        cm = (duration/2) / 29.1; // Divide by 29.1 or multiply by 0.0343
        inches = (duration/2) / 74; // Divide by 74 or multiply by 0.0135
        for (i=0; i<5; i++)
        {
               sum=sum+inches;
               avg = sum/5;
        }
        Serial.print(avg);
        Serial.print("Avg, ");
        Serial.print(cm);
        Serial.print("cm");
        Serial.println();
        Serial.print(inches);
        Serial.print("in");
        Serial.println();

        delay(250);
}

Circuit Diagram: