int R = 12;
int G = 11;

int spk = 10;
int frq1 = 500;
int frq2 = 1000;

int E4 = 9;
int E3 = 8;
int E2 = 7;
int E1 = 6;

int C1, C2, C3, C4;

int codeStatus = 0;

int button = 5;
int ButtonStatus = 0;

void setup() {
  Serial.begin(9600);
  pinMode(R, OUTPUT);
  pinMode(G, OUTPUT);

  pinMode(E4, INPUT);
  pinMode(E3, INPUT);
  pinMode(E2, INPUT);
  pinMode(E1, INPUT);

  pinMode(button, INPUT_PULLUP);
  
  Serial.println("Bitte gebe den richtigen Code ein!");
}

void loop() {
  C1 = digitalRead(E1);
  C2 = digitalRead(E2);
  C3 = digitalRead(E3);
  C4 = digitalRead(E4);
  
if(C1 == 1 && C2 == 0 && C3 == 0 && C4 == 1){
  codeStatus = 1;
}
  else{
    codeStatus = 0;
  }

  
ButtonStatus = digitalRead(button);

if(ButtonStatus == 1){
  if(codeStatus == 1){
    Serial.println(codeStatus);
    Serial.println("Richtiger Code erkannt!");
    digitalWrite(G, 1);
    tone(spk, frq1);
    delay(1000);
    digitalWrite(G, 0);
    noTone(spk);
    Serial.println("Tür wird geöffnet!");

    C1 = C2 = C3 = C4 = 0;
  }
  else{
    Serial.println("Falscher Code!");
    digitalWrite(R, 1);
    tone(spk, frq2);
    delay(1000);
    digitalWrite(R, 0);
    noTone(spk);
  }
}
}