int state;      // Variablen
bool tz;
bool atz;
int Z=0;
                           //IVAN IVANOV
int s1;
int s2;
int s3;
int s4;

void setup() 
{
  // put your setup code here, to run once:
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, INPUT_PULLUP);
  Serial.begin(9600);
}

  void loop() 
  {

    // put your main code here, to run repeatedly:
      tz = (digitalRead(7)== LOW);
      if((tz!=atz) && (tz=HIGH))
      {state ++;}

      atz = tz;
      if(state>=4)
      {state=1;}

      switch(state)
      {
        case 1:
        s1++;
        digitalWrite(6, HIGH);
        digitalWrite(5, LOW);
        digitalWrite(4, LOW);

        case 2:
        s2++;
        digitalWrite(6, LOW);
        digitalWrite(5, HIGH);
        digitalWrite(4, LOW);

        case 3:
        s3++;
        digitalWrite(6, LOW);
        digitalWrite(5, LOW);
        digitalWrite(4, HIGH);


          case 4:
          digitalWrite(6, LOW);
          digitalWrite(5, LOW);
          digitalWrite(4, LOW);
      }



    }