lab3.ino

const int lockpin = 12;
const int blinkpin = 13;
const int combs[4] = {4,5,6,7};

const int combination[3] = {0,1,2}, combinationLength = 3, inputLength = 100;
int input[100], index, prev[4];
boolean locked = true;

void setup() {
  pinMode(lockpin, OUTPUT);
  pinMode(blinkpin, OUTPUT);
  for (int i=0;i<4;++i) pinMode(combs[i], INPUT);
  Serial.begin(56700);
}

void loop() {
  int cur[4];
  for (int i=0;i<4;++i) {
    cur[i] = digitalRead(combs[i]);
    if (cur[i] != prev[i] && cur[i] == 1) {
      Serial.println(i, DEC);
      if (i < 3) {
        if (locked && index < inputLength) {
          input[index++] = i;
        }
      } else {
        if (locked) {
          boolean matches = false;
          if (index == combinationLength) {
            matches = true;
            for (int j=0;j<combinationLength;++i) {
              if (input[j] != combination[j]) matches = false;
            }
          }
          if (matches) {
            success();
          } else {
            failCode();
          }
        } else {
           locked = true;
        }
      }
    }
  }
  
  for (int i=0;i<4;++i) {
    prev[i] = cur[i];
  }
  digitalWrite(lockpin, locked ? HIGH : LOW);
  delay(15);
}

void success() {
  digitalWrite(lockpin, LOW);
  digitalWrite(blinkpin, HIGH);
  delay(100);
  digitalWrite(blinkpin, LOW);
  locked = false;
  index = 0;
}

void failCode() {
  digitalWrite(blinkpin, HIGH);
  for (int i=0;i<=4;++i) {
    delay(200);
    digitalWrite(blinkpin, i % 2);
  }
  locked = true;
  index = 0;
}