// defines pins numbers
const int trigPin = 12;
const int echoPin = 2;
const int buzzer  = 13;
const int ledPin  = 7;


// defines variables
long duration;
int distance;
int safetyDistance;

void setup() {

pinMode(trigPin, OUTPUT);

// Sets the trigPin as an Output

pinMode(echoPin, INPUT);
// Sets the echopin as an Input
pinMode(buzzer, OUTPUT);
pinMode(ledPin, OUTPUT);
Serial.begin(9600);
// Starts the serial communication
}

void loop() {

// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);

// Sets the trigPin on HIGH state for 10 micro seconds

digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin,LOW);

// Reads the echoPin, returns the sound wave travel time in microseconds
duration= pulseIn(echoPin, HIGH);

// Calculating the distance
distance = duration*0.034/2;

safetyDistance = distance;
if (safetyDistance <= 10) {

digitalWrite(buzzer, HIGH);
digitalWrite(ledPin, HIGH);
}
else
{
digitalWrite(buzzer, LOW);
digitalWrite(ledPin, LOW);
}
// Prints the distance on the Serial Monitor
Serial.print("distance");
Serial.println(distance);
}