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

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

void setup()

{
Serial.begin (9600);
pinMode(triggerPin, OUTPUT);
pinMode(echoPin, INPUT);
}

void loop()

{
digitalWrite(triggerPin, LOW);
delayMicroseconds(3);
digitalWrite(triggerPin, HIGH);
delayMicroseconds(6);
digitalWrite(triggerPin, LOW);
delayMicroseconds(9);

pinMode(echoPin, INPUT);
duration = pulseIn(echoPin, HIGH);

inches = (duration/2) / 74; // Divide by 74 or multiply by 0.0135
cm = (duration/2) / 29.1; // Divide by 29.1 or multiply by 0.0343

for (i=0; i<10; i++)
{
sum= sum+inches;
avg = sum/10;
}
Serial.print(avg);
Serial.print("Avg, ");
Serial.print(cm);
Serial.print("cm");
Serial.println();
Serial.print(inches);
Serial.print("in");
Serial.println();

delay(1000);
}