float t;
float s;
#define Trigerpin 7
#define Echopin 6
 

void setup() {

  pinMode(Trigerpin,OUTPUT);
  pinMode(Echopin,INPUT);
  Serial.begin(9600);

}

void loop() {
  digitalWrite(Trigerpin,HIGH);
  delayMicroseconds(10);
  digitalWrite(Trigerpin,LOW);
  t=pulseIn(Echopin,HIGH);
  s=(340*t)/2/10000;
  Serial.println(s);
  delay (200);

}