@t=map eval"sub{\$n=~tr/1234/$_/;\$n}",((1243,1432)x2,1243,4321)x4;map{$n= "1234$_";map&$_,@t}map{$_,join"",(split/(....)/)[1,5,3]}341221434321, 341223414123,342121434312,431221433421,432121433412,432124133142 #### sub p{my($c,$i)=@_;$i==16?$c?():"":(map("0$_",p($c,$i+1)),map"7$_",p($c-1,$i+1) )}@t=map eval"sub{\$n=~tr/1234/$_/;\$n}",((1243,1432)x2,1243,4321)x4;@f=map{$n= "1234$_";map&$_,@t}map{$_,join"",(split/(....)/)[1,5,3]}341221434321, 341223414123,342121434312,431221433421,432121433412,432124133142;$_=pop;for$m( p($_)){++$s{$m&$_}for@f}print 0+grep$_<2,values%s