#define Buzzer 4
#define trigPin 5
#define echoPin 6
long duration;
int distance = 0;
void setup()
{
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT); 
pinMode(Buzzer, OUTPUT); 
Serial.begin(9600); 
}
void loop()
{
digitalWrite(trigPin, HIGH);
delayMicroseconds(10); 
digitalWrite(trigPin, LOW); 
duration = pulseIn(echoPin, HIGH); 
distance= duration*0.034/2; 
if (distance <= 100) 
{
Serial.println(distance); 
digitalWrite(Buzzer,HIGH);
delay(distance);
digitalWrite(Buzzer,LOW);
delay(distance);
}
}