void setup() {
  // put your setup code here, to run once:
  DDRA=0XFF;
  DDRC=0XFF;
  DDRD=0X00;
  attachInterrupt(digitalPinToInterrupt(18),SW1, FALLING);
  attachInterrupt(digitalPinToInterrupt(19),SW2, FALLING);
  attachInterrupt(digitalPinToInterrupt(20),SW3, FALLING);
  attachInterrupt(digitalPinToInterrupt(21),SW4, FALLING);
}
int ledout=0;
int fnd[9]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80};
int number=1;
int mode=0;
int mode_cnt=0;
void SW1() {
  mode_cnt=0;
  mode=1;
}
void SW2() {
  mode_cnt=1;
  mode=2;
}
void SW3() {
  if(mode_cnt==1) {
    delay(300);
    ledout--;
    number--;
  }
}
void SW4() {
  ledout=0;
  number=0;
  mode_cnt=0;
  mode=0;
}
void loop() {
  // put your main code here, to run repeatedly:
  switch(mode) {
    case 0:
      PORTA=0X00;
      PORTC=fnd[0];
      break;
    case 1:
      PORTA=1<<ledout;
      PORTC=fnd[number];
      delay(300);
      ledout++;
      number++;
      if(ledout>7) {
        number=1;
        ledout=0;
      }
      break;
    case 2:
      PORTA=1<<ledout;
      PORTC=fnd[number];
      if(ledout<0) {
        number=8;
        ledout=7;
      }
      break;
  }
}