//PD = Pin digit, PD1 is the most left position and PD4 is the most right
// PD1 PD2 PD3 PD4
int pd1 = 1;
int pd2 = 1;
int pd3 = 1;
int pd4 = 1;

int reset = 13;

int a = 0;
int b = 0;
int c = 0;
int d = 0;

int u1 = 0;
int u2 = 0;
int u3 = 0;
int u4 = 0;

#include <TM1637.h>

const int CLK = 9;
const int DIO = 8;

TM1637 tm(CLK, DIO);

void setup() {

  tm.init();
  tm.set(BRIGHT_TYPICAL);


  Serial.begin(9600);
  // pinMode initialization:
  pinMode(2, INPUT_PULLUP);
  pinMode(3, INPUT_PULLUP);
  pinMode(4, INPUT_PULLUP);
  pinMode(5, INPUT_PULLUP);
  pinMode(reset, INPUT_PULLUP);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
}

void loop() {
  Serial.print(u1);  Serial.print(" | ");  Serial.print(u2);  Serial.print(" | ");   Serial.print(u3);  Serial.print(" | ");  Serial.println(u4); 
  tm.display(0,a);   tm.display(1,b);   tm.display(2,c);  tm.display(3,d);
  
  
  // all the green button
  if (digitalRead(2) == 0) {a += 1; delay(200);}
  if (digitalRead(3) == 0) {b += 1; delay(200);}
  if (digitalRead(4) == 0) {c += 1; delay(200);}
  if (digitalRead(5) == 0) {d += 1; delay(200);}

  // reset button
  if (digitalRead(reset) == 0) {a = 0; b = 0; c = 0; d = 0; delay(200);}

  // pin digit combination logic
  if (a == pd1) {u1 = 1;} else {u1 = 0;}
  if (b == pd2) {u2 = 1;} else {u2 = 0;}
  if (c == pd3) {u3 = 1;} else {u3 = 0;}
  if (d == pd4) {u4 = 1;} else {u4 = 0;}


  // pin digit authentication from pin digit combination
  int auth = u1 + u2 + u3 + u4;
  if (auth == 4) {digitalWrite(10,HIGH);digitalWrite(11,LOW);} 
  else {digitalWrite(10,LOW);digitalWrite(11,HIGH);}
}