use v5.36;

undef $/;
sub slurp { local @ARGV = shift; <> }
my %corres;
for my ($v, $k) (split "\n", slurp 'corres') {$corres{$k} = $v}

$_= slurp 'A';
s{ (?<url>
		https://sws.geonames.org/
		(?<key> [^/]+ )
		/about.rdf )
}{ $corres{$+{key}} // $+{url} }gex;
print;