Taking two lines as the input

Taking two lines as the input

If I have two lines in a file that look like this:
1 222 333
4 555 666
Is there a way to access these all at once such that:
$1 = 1, $2 = 222, $3 = 333, $4 = 444, $5 = 555, $6 = 666
Any thoughts?