Sorry about the flooding, but this is an interesting problem. The first of these is only one stroke behind Ton.
-l $_=$"x2**pop;s-.-s,,,,s,$,/\\,,print,s,(?<=\\)..,$&^h9^gE,eg-ge -l $_=$"x2**pop;s-.-/./,$_="$'/\\",print,s,(?<=\\)..,$&^h9^gE,eg-ge A minor improvement to "five substitutions": -l s--$"x$^F**pop-e,s-.-s,,,,s,$,/\\,,print,s,(?<=\\)..,$&^h9^gE,ge-ge /-\
