//gives a random number between 0 and 9

int dataPin = PB0; 
int clockPin = PB2;
int latchPin = PB1;
int button = PB4;
void setup() {
  pinMode(dataPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
  pinMode(button, INPUT_PULLUP);
}
bool firstTime= true;

void loop() {
  while (digitalRead(PB4) == HIGH) {
    // do nothing
  }
  if (firstTime) {
    randomSeed(micros());// to increase randomness
    firstTime = false;
  }
  for (byte i = 0; i < 10; i++) {
    int num = random(0, 10);//gives a random number from 1 to 6
    displayNumber(num);
    delay(50 + 20 * i);
  }
}
void displayNumber(byte number) {
  int pattern=0b00000000;
  if(number==0){
    pattern = 0b00000011;//0
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==1){
  pattern = 0b10011111;//1
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==2){
   pattern = 0b00100101;//2
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==3){
   pattern = 0b00001101;//3
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==4){
   pattern = 0b10011001;//4
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==5){
   pattern = 0b01001001;//5
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==6){
   pattern = 0b01000001;//6
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==7){
   pattern = 0b00011111;//7
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==8){
   pattern = 0b00000001;//8
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}

  if(number==9){
   pattern = 0b00001001;//9
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
  delay(50);}
}