Multi variable assignment -
Since only one value is specified on each line only the first variable is populated. only $a and $b have a value assigned. So $a contains 123, $b contains 456, $c and $d are null so the write host would be 123 456.
Multi variable assignment -
Since only one value is specified on each line only the first variable is populated. only $a and $b have a value assigned. So $a contains 123, $b contains 456, $c and $d are null so the write host would be 123 456.