enum M{M;int i,j,k,a[];{for(;i++<1e4;j=i){for(a=new int[k=10];j>0;j/=k)a[j%k]++;String s="",t=s;for(;j++<9;)if(a[j]>1){s+=j;t=j+t;a[j]-=2;j=-1;}for(;j-->0;)k=a[j]>0?k==10?j:i:k;if(k<i)System.out.println(k>9?s+t:s+k+t);}}}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).