int btn=12;
int data=0;
int sayac=0;



void setup() {
  pinMode(btn, INPUT);
   pinMode(2, OUTPUT);
    pinMode(3, OUTPUT);
     pinMode(4, OUTPUT);
 Serial.begin(9600);
}

void loop () 
{
  data=digitalRead(btn);
  if(data==1)
  {
    sayac=sayac+1; 
    delay(300);
  }
  Serial.println(sayac); 
switch (sayac)
    { 
        case 0:
      {
        digitalWrite(2, HIGH);
        digitalWrite(3, LOW);
        digitalWrite(4, LOW);
        break;
      }
        
        case 1:
      {
        digitalWrite(2, LOW);
        digitalWrite(3, HIGH);
        digitalWrite(4, LOW);
        break;
      }
      

        case 2:
      {
        digitalWrite(2, LOW);
        digitalWrite(3, LOW);
        digitalWrite(4, HIGH);
        break;
      }
        case 3:
      {
        digitalWrite(2, HIGH);
        digitalWrite(3, HIGH);
        digitalWrite(4, HIGH);
        break;
      }
      case 4:
      { 
        sayac=0;
        delay(100);
        break;
      }


    }
}