#define Ap 10
#define Am 11
#define Bp 9
#define Bm 8
int A=0;
void setup() {
  pinMode(Ap, OUTPUT); pinMode(Am, OUTPUT);
  pinMode(Bp, OUTPUT); pinMode(Bm, OUTPUT);
}

void loop() {
  for (int i = 0; i < 25; i++) { 
    langkahKanan();
    delay(5);
  }
  delay(500); 

  for (int i = 0; i < 0; i--) { 
    langkahKiri();
    delay(5);
  }
  A=0;
  delay(500); 
}

void langkahKanan() {
  digitalWrite(Ap, HIGH); digitalWrite(Am, LOW);
  digitalWrite(Bp, HIGH); digitalWrite(Bm, LOW);
  delay(5);

  digitalWrite(Ap, LOW); digitalWrite(Am, HIGH);
  digitalWrite(Bp, HIGH); digitalWrite(Bm, LOW);
  delay(5);

  digitalWrite(Ap, LOW); digitalWrite(Am, HIGH);
  digitalWrite(Bp, LOW); digitalWrite(Bm, HIGH);
  delay(5);

  digitalWrite(Ap, HIGH); digitalWrite(Am, LOW);
  digitalWrite(Bp, LOW); digitalWrite(Bm, HIGH);
  delay(5);
}

void langkahKiri() {
  digitalWrite(Ap, HIGH); digitalWrite(Am, LOW);
  digitalWrite(Bp, LOW); digitalWrite(Bm, HIGH);
  delay(5);

  digitalWrite(Ap, LOW); digitalWrite(Am, HIGH);
  digitalWrite(Bp, LOW); digitalWrite(Bm, HIGH);
  delay(5);

  digitalWrite(Ap, LOW); digitalWrite(Am, HIGH);
  digitalWrite(Bp, HIGH); digitalWrite(Bm, LOW);
  delay(5);

  digitalWrite(Ap, HIGH); digitalWrite(Am, LOW);
  digitalWrite(Bp, HIGH); digitalWrite(Bm, LOW);
  delay(5);
}