#define trig 9
#define echo 10
#define motor1 5
#define motor2 6

int speed = 0;
int ultra(int trg, int ech){
  digitalWrite(trg, LOW);
  delayMicroseconds(2);
  digitalWrite(trg, HIGH);
  delayMicroseconds(10);
  digitalWrite(trg, LOW);
int duration = pulseIn(ech,HIGH);
  int distance = duration * 0.034/2;
  return distance;
}

void setup() {
  pinMode(trig,OUTPUT);
  pinMode(echo,INPUT);
  pinMode(motor1, OUTPUT);
  pinMode(motor2, OUTPUT);
  Serial.begin(9600);

}

void loop() {
  int a = ultra(trig,echo);
  if (a > 40){
  for (int speed = 0; speed <= 255; speed++) { 
  analogWrite(motor1, speed);
  digitalWrite(motor2, LOW);
  delay(10);
  int a = ultra(trig,echo); 
  if(a < 30){
  break;
  }
  Serial.println(a);
  Serial.println("kumalala");
  while(speed == 255){
  digitalWrite(motor1, HIGH);
  digitalWrite(motor2, LOW);
  Serial.println(a);
  Serial.println("kumalala");
  int a = ultra(trig,echo); 
  if(a < 30){
    break;
  }
  }}
}

if (a < 30){
  digitalWrite(motor1, 0);
  analogWrite(motor2, 0);
}

}