Adapted from (tye)Re: varying length multi-dimensional hashes:

sub setHoH {
    my( $hashref, $val, @keys )= @_;
    my $ref= \$hashref;
    for(  @keys  ) {
        $ref= \$$ref->{$_};
    }
    $$ref= $val;
}
@array= qw/one two three/;
setHoh( \%hash, 1, @array );
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