> #include<stdio.h>
> main()
> { int a[6],b[6],i,j,t,t1,t2;
>   for(i=0;i<6;i++)
>   { scanf("%d%d",&a[i],&b[i]);
>     if(a[i]<b[i])
>     { t=a[i];
>       a[i]=b[i];
>       b[i]=t;}
>    }
> for(i=0;i<5;i++)
>  for(j=0;j<5-i;j++)
>  { if(a[j]<a[j+1])
>     { t1=a[j];
>       a[j]=a[j+1];
>       a[j+1]=t1;
>        t2=b[j];
>       b[j]=b[j+1];
>       b[j+1]=t2;}
>   }
> i=0;
> while(i<6)
> { if((a[i]!=a[i+1])||(b[i]!=b[i+1])) break;
>   else i+=2;
>  }
> if(i==6)
>  {  if(a[0]==a[2])
>     {if((a[0]==a[2])||(a[0]==b[2])||(b[0]==a[2])||(b[0]==b[2]))
>       {if((a[2]==a[4])||(a[2]==b[4])||(b[2]==a[4])||(b[2]==b[4]))
>         { if((a[0]==a[4])||(a[0]==b[4])||(b[0]==a[4])||(b[0]==b[4]))
>            printf("POSSIBLE\n");
>          else printf("IMPOSSIBLE\n");
>          }
>        else printf("IMPOSSIBLE\n");
>       }
>     else printf("IMPOSSIBLE\n");
>    }
>    else printf("IMPOSSIBLE\n");
>    }
>    else printf("IMPOSSIBLE\n");
> getch();
> }