If you put the match operation in list context, you can gobble up the matched items:

if( my($a, $c) = $string =~ /(a).*(c)/ ) {
    print "a=$a c=$c\n";
}
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To store them in a hash,use a hash slice to assign them:

@result{"a","b"} = $string =~ /(a).*(c)/;
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