Arduino Cybot Light Follower[Test Code 4]

//http://www.youtube.com/watch?v=w7Sdtg9mHGM

//Motor control pins

int rightfor = 11;
int rightback = 10;
int leftfor = 9;
int leftback = 6;

//Variables

int diff = 0;
int correctionspeed = 0;

void setup(){

  Serial.begin(9600);

  pinMode(A0, INPUT);
  pinMode(A1, INPUT);
  pinMode(rightfor, OUTPUT);
  pinMode(rightback, OUTPUT);
  pinMode(leftfor, OUTPUT);
  pinMode(leftback, OUTPUT);

}

void loop(){

  int leftlight = analogRead(A1);
  int rightlight = analogRead(A0);

  leftlight = map(leftlight, 0, 950, 0, 255);
  rightlight = map(rightlight, 0, 890, 0, 255);

  leftlight = constrain(leftlight, 0, 255);
  rightlight = constrain(rightlight, 0, 255);

  if( analogRead(A0) > 26 && analogRead(A1) > 26){

  diff = leftlight - rightlight;
  if(diff < 0) diff = (-1) * diff;
  correctionspeed = diff + 170;
  correctionspeed = constrain(correctionspeed, 0, 255);

  if(diff < 26 ){

  analogWrite(rightfor, 225);
  analogWrite(rightback, 0);
  analogWrite(leftfor, 225);
  analogWrite(leftback, 0);

  }

  if ( leftlight > rightlight){

  analogWrite(rightfor, correctionspeed);
  analogWrite(rightback, 0);
  analogWrite(leftfor, 0);
  analogWrite(leftback, 0);



  }
  else if ( rightlight > leftlight){

    analogWrite(rightfor, 0);
    analogWrite(rightback, 0);
    analogWrite(leftfor,  correctionspeed);
    analogWrite(leftback, 0);
  }


  }
  else {

    analogWrite(rightfor, 0);
    analogWrite(rightback, 0);
    analogWrite(leftfor, 0);
    analogWrite(leftback, 0);



  }
}