Method and apparatus for encoding video and method and apparatus for decoding video by considering skip and split order

A method of decoding a video includes: receiving and parsing a bitstream of encoded video data; extracting, from the bitstream, information about a maximum size of a coding unit being a data unit in which a picture is decoded, information about an order of split information and skip mode information about coding units according to depths, and, according to the order of the split information and the skip mode information, information about a coded depth and an encoding mode and encoded video data according to a maximum coding unit of the picture; and based on the extracted information about the maximum size of the coding unit and the information about the coded depth and the encoding mode, decoding the encoded video data of the picture according to coding units having a tree structure including coding units of coded depths.