Why are you removing the colons?

map {s/\\://g;$_}
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should be

map { (my $s = $_) =~ s/\\(.)/$1/sg; $s }
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Update: hum... The OP did show a lack of colons in the desired output. If that's truly what he wants,

map {s/\\://g;$_}
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should be

map { my $s = $_; $s =~ s/\\(.)/$1/sg; $s =~ s/://g; $s }
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