A nonvolatile memory includes a first sub-block defined by a first string select line and a first word line; a second sub-block defined by a second string select line different from the first string select line and a second word line different from the first word line; a first vacant block defined by the first string select line and the second word line; and a second vacant block defined by the second string select line and the first word line. First data is programmed in the first sub-block with, second data is programmed in the second sub-block, and no data is programmed in the first vacant block and the second vacant block.