void setup() {
  //#define  in1 9
#define in2 8
#define in3 7
#define in4 6
#define enA 10
#define  enB 5
 int M1_Speed = 80; // speed of motor 1
 int M2_Speed = 80; // speed  of motor 2
 int LeftRotationSpeed = 250;  // Left Rotation Speed
 int RightRotationSpeed  = 250; // Right Rotation Speed


 void setup() {

  pinMode(in1,OUTPUT);
  pinMode(in2,OUTPUT);
  pinMode(in3,OUTPUT);
  pinMode(in4,OUTPUT);

    pinMode(enA,OUTPUT);
    pinMode(enB,OUTPUT);

      pinMode(A0, INPUT);  // initialize Left sensor as an input
      pinMode(A1, INPUT); // initialize  Right sensor as an input

}

void loop() {

  int LEFT_SENSOR  = digitalRead(A0);
  int RIGHT_SENSOR = digitalRead(A1);

 if(RIGHT_SENSOR==0  && LEFT_SENSOR==0) {
    forward(); //FORWARD
}

  else if(RIGHT_SENSOR==0  && LEFT_SENSOR==1) {
    right(); //Move Right
 }

  else if(RIGHT_SENSOR==1  && LEFT_SENSOR==0) {
    left(); //Move Left
}

  else if(RIGHT_SENSOR==1  && LEFT_SENSOR==1) {
    Stop();  //STOP
 }
}



void forward()
{
           digitalWrite(in1, HIGH);
            digitalWrite(in2, LOW);            digitalWrite(in3, HIGH);
            digitalWrite(in4, LOW);

                analogWrite(enA, M1_Speed);
                analogWrite(enB,  M2_Speed);
}

void backward()
{
            digitalWrite(in1, LOW);
            digitalWrite(in2, HIGH);
            digitalWrite(in3, LOW);
            digitalWrite(in4, HIGH);

                analogWrite(enA, M1_Speed);
               analogWrite(enB, M2_Speed);
}

void right()
{
            digitalWrite(in1,  LOW);
            digitalWrite(in2, HIGH);
            digitalWrite(in3, HIGH);
            digitalWrite(in4, LOW);

                analogWrite(enA, LeftRotationSpeed);
                analogWrite(enB, RightRotationSpeed);
}

void left()
{
            digitalWrite(in1, HIGH);
            digitalWrite(in2, LOW);
            digitalWrite(in3, LOW);
            digitalWrite(in4, HIGH);

                analogWrite(enA, LeftRotationSpeed);
                analogWrite(enB,  RightRotationSpeed);
}

void Stop()
{
            digitalWrite(in1,  LOW);
            digitalWrite(in2, LOW);
            digitalWrite(in3, LOW);
            digitalWrite(in4, LOW);
}
 put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}