Remote Control bot

byte fw=2,bw=3,lt=4,rt=5;
byte la=8,lb=9,ra=10,rb=11;
byte f=0,r=0,l=0,b=0,state=0;
void setup() {
  pinMode(fw,INPUT);
  pinMode(bw,INPUT);
  pinMode(lt,INPUT);
  pinMode(rt,INPUT);
  pinMode(lb,OUTPUT);
  pinMode(la,OUTPUT);
  pinMode(ra,OUTPUT);
  pinMode(rb,OUTPUT);
  Serial.begin(9600);
}
byte reader(){
 f=0;
 r=0;
 l=0;
 b=0;
 f=digitalRead(fw);
 if(f==1)
 {
  Serial.println("out1");
  return 10;
 }
 b=digitalRead(bw);
 if(b==1)
 {
  Serial.println("out2");
  return 20;
 }
 l=digitalRead(lt);
 if(l==1)
 {
  Serial.println("out3");
  return 30;
 }
 r=digitalRead(rt);
 if(r==1)
 {
  Serial.println("out4");
  return 40;
 }
 return 0;
}
void clearstate()
{
 digitalWrite(ra,0);
 digitalWrite(rb,0);
 digitalWrite(la,0);
 digitalWrite(lb,0); 
}
void loop(){
  state=reader();
  while(state==10)
  {
    digitalWrite(la,1);
    digitalWrite(lb,0);
    digitalWrite(ra,1);
    digitalWrite(rb,0);
    state=reader();
  }
  clearstate();
  while(state==20)
  {
    digitalWrite(la,0);
    digitalWrite(lb,1);
    digitalWrite(ra,0);
    digitalWrite(rb,1);
    state=reader();
  }
  clearstate();
  while(state==30)
  {
    digitalWrite(la,0);
    digitalWrite(lb,1);
    digitalWrite(ra,1);
    digitalWrite(rb,0);
    state=reader();
  }
  clearstate();
  while(state==40)
  {
    digitalWrite(la,1);
    digitalWrite(lb,0);
    digitalWrite(ra,0);
    digitalWrite(rb,1);
    state=reader();
  }
  clearstate();  
}