Infection (389)

Other names: Sukoro

Fill some cells with a number from 1 to 4. All numbered cells must be orthogonally connected. Orthogonally adjacent cells cannot contain the same number. Each number must indicate the number of orthogonally adjacent numbered cells. Some numbers are given to you. Some cells may be marked with a '×'; those cells must not be filled with a number.

Reference: WPF (1)