perl -le'$#a=$d=pop;sub r{int rand 9}while($c<$d){$c++if$a[$c]==r;@a[$c..$d]=(r)x$d;print@a}' 10

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perl -e'$#a=$d=pop;sub r{int rand 9}while($c<$d){$c++if$a[$c]==r;@a[$c..$d]=(r)x$d;print@a,"\r"}print$/' 10

##</code><code>##

perl -e'$#a=$d=pop;sub r{int rand 9}while($c<$d){$c++if$a[$c]==r;for(0..1e4){@a[$c..$d]=(r)x$d;print@a,"\r"}}print$/' 10