#define trigPin 12
#define echoPin 13
int b;
void setup(){

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

void loop(){

  float Temp, Dist, B;

  digitalWrite(trigPin, LOW);
  delayMicroseconds(1);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(1);
  digitalWrite(trigPin, LOW);

  Temp = pulseIn(echoPin, HIGH);

  Dist = (Temp/2) / 29.1;
  b = Dist;

  switch(b){
  case 10:
    digitalWrite(11,HIGH);
    break;
  case 11:
    digitalWrite(10, HIGH);
    break;
  default:
  }
}