int i,j;                                                 
int count=0;                                             
int number;                                              
unsigned long time=0;                                    
const byte num[10]=                                      
      { B11000000, B11111001, B10100100, B10110000, B10011001,
        B10010010, B10000010, B11111000, B10000000, B10010000 };
const int seg[]={ 2,3,4,5,6,7,8,9 };                     
const int digit[]={ 10,11,12,13 };                       

void setup()
{
     for(i=0;i<8;i++)
         pinMode(seg[i],OUTPUT);                         
     for(i=0;i<4;i++)
     {
         pinMode(digit[i],OUTPUT);                       
         digitalWrite(digit[i],HIGH);                    
     }
}

void loop()
{
     number=count; 
     for(i=3;i>=0;i--)                                   
     {
         for(j=0;j<8;j++)                                
         {
             if(bitRead(num[number%10],j))               
                digitalWrite(seg[j],HIGH);               
             else
                digitalWrite(seg[j],LOW);                
         }
         digitalWrite(digit[i],LOW);                     
         delay(5);                                       
         digitalWrite(digit[i],HIGH);                    
         number=number/10;                               
         if(millis()-time>=1000)                         
         {
            time=millis();                               
            count++;                                     
            if(count>9999)                               
               count=0;                                  
         }
     }
}