Rebuild x from residues x mod pᵢ. Solve each mixed-radix digit
aᵢ in turn (subtract the partial, multiply by the prefix-product inverse mod pᵢ)
and accumulate x = a₀ + a₁p₀ + a₂p₀p₁ + …
pᵢ; the running value x = Σ aᵢ·Wᵢ
(with prefix products Wᵢ = p₀·…·pᵢ₋₁) accumulates as digits appear.
See junior.md and professional.md for the uniqueness and correctness proofs.