#include <stdio.h>

#define maxn 1000001
        long n;
       short result[31],b[maxn];
       int tr[maxn];
      long count,i,j;

main()
{
       scanf("%ld",&n);
      for (i=0;i<n;i++) b[i]=0;
      b[1%n]=1;
      tr[1%n]=0;
      if (n!=1) b[2%n]=2;
      tr[2%n]=0;
      count=1;
       while (b[0]==0 && count <30)
      {
          count++;
          for (i=1;i<n;i++)
         if  (b[i]!=0)
         {
             if (b[(i*10+1)%n]==0)
            {
                b[(i*10+1)%n]=1;
               tr[(i*10+1)%n]=i;
            };
             if (b[(i*10+2)%n]==0)
            {
                b[(i*10+2)%n]=2;
               tr[(i*10+2)%n]=i;
            };
         }
      }
      if (b[0]==0)
      {
          printf("Impossible");
      }
      else
      {
          i=0;
         j=1;
         result[j]=b[i];
         while (tr[i]!=0)
         {
             i=tr[i];
            j++;
            result[j]=b[i];
         }
         for (i=j;i>0;i--) printf("%d",result[i]);
      }
    getchar();
}

74147

21221212122222222

When i had wa 10 i found out that my solution on test like 101 gives me 1212 instead of 1111. It doesnt helped me on this test, but i found mistake anyway

thanks a lot!