const int trigPin =A5;
const int echoPin = A4;
int a;
int b;
int c;
int d;
long duration;
int distance;
void init_motors(){
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(7, OUTPUT);

  pinMode(6, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(8, OUTPUT);

  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
}

void forward(){
  digitalWrite(4, HIGH);
  digitalWrite(12, HIGH);
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
}

void reverse(){
  digitalWrite(4, LOW);
  digitalWrite(12, LOW);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
}

void right(){
  digitalWrite(4, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(7, LOW);
  digitalWrite(12, LOW);
}

void left(){
  digitalWrite(7, HIGH);
  digitalWrite(12, HIGH);
  digitalWrite(4, LOW);
  digitalWrite(8, LOW);
}

void left_forward(){
  digitalWrite(12, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(7, LOW);
  digitalWrite(4, LOW);
}

void right_forward(){
  digitalWrite(4, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(7, LOW);
  digitalWrite(12, LOW);
}

void right_reverse(){
  digitalWrite(8, HIGH);
  digitalWrite(7, LOW);
  digitalWrite(12, LOW);
  digitalWrite(4, LOW);
}

void left_reverse(){
  digitalWrite(7, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(4, LOW);
  digitalWrite(12, LOW);
}

void stop(){
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
  digitalWrite(4, LOW);
  digitalWrite(12, LOW);
}


void setup(){
  pinMode(trigPin,OUTPUT);
pinMode(echoPin,INPUT);
pinMode(A0,INPUT);
Serial.begin(9600);
  
  init_motors();
}
void loop(){
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
 
  duration = pulseIn(echoPin, HIGH);
 
  distance = duration * 0.034 / 2;
  a=digitalRead(A0);
  b=digitalRead(A1);
  c=digitalRead(A2);
  d=digitalRead(A3);
  
  if(a==0)
  {
    digitalWrite(11,HIGH);
    digitalWrite(10,HIGH);

  }
  else
  {
     digitalWrite(11,LOW);
     digitalWrite(10,LOW);
  }
  if(c==1)
  {
    digitalWrite(5,HIGH);
    digitalWrite(9,HIGH);
   

  }
  else
  {
     digitalWrite(5,LOW);
     digitalWrite(9,LOW);
     
  }
  Serial.println(b);

  if(distance>10){
    digitalWrite(A3,HIGH);
  }
  else
  { digitalWrite(A3,LOW);}

  
  if(distance<10){
    digitalWrite(9,HIGH);
  } else{
 
  digitalWrite(9,LOW);
  }
forward();
  if(distance<10&&distance>0){
    stop();
   reverse();
    left();
   
    stop();
   reverse();
    left();
    
    

  }
}