# Meaning of pseudocode "$(C, S):=$"

I've seen pseudocode of this form in the Montgomery multiplication related theses: $$(C, S) := a[j]*b[0]+C$$.

What's the meaning of "$$(C, S):=$$", or what is the real code that was converted from this pseudocode like?

I believe that the meaning is "compute the $2n$-bit value $a[j]*b[0] + C$, and then assign the top $n$ bits to $C$ and the bottom $n$ bits into $S$