#include <avr/io.h>
#include <util/delay.h>
#define F_CPU 8000000

int main()
{
    DDRC = 0xFF;
    DDRA = 0x00;
    PORTA = 0xFF;
    int delay = 50;
    while(1)
    {
        if (!(PINA&_BV(7)))
        {
            PORTC = 0b00001100;
            _delay_ms(delay);
            PORTC = 0b00000110;
            _delay_ms(delay);
            PORTC = 0b00000011;
            _delay_ms(delay);
            PORTC = 0b00001001;
            _delay_ms(delay);
        }
        else if (!(PINA&_BV(6)))
        {
            PORTC = 0b00001001;
            _delay_ms(delay);
            PORTC = 0b00000011;
            _delay_ms(delay);
            PORTC = 0b00000110;
            _delay_ms(delay);
            PORTC = 0b00001100;
            _delay_ms(delay);
        }
        else if (!(PINA&_BV(5))) { delay += 10; _delay_ms(200); }
        else if (!(PINA&_BV(4))) { if (delay > 50) delay -= 10; _delay_ms(200); }
        else PORTC = 0x00;
    }
    return 0;
}