A nonvolatile memory includes a memory array. The memory array is connected to m word lines and (2+n) bit line pairs. These bit line pairs include an erase bit line pair, a program bit line pair and n data bit line pairs. Each word line is connected with (2+n) differential cells of a corresponding row. The (2+n) differential cells include an erase flag differential cell, a program flag differential cell and n data differential cells. The erase flag differential cell is connected with the erase bit line pair. The program flag differential cell is connected with the program line pair. The n data differential cells are connected with the data line pairs. The n data differential cells are determined as erased cells or programmed cells according to setting conditions of the erase flag differential cell and the program flag differential cell.