In a solution area which has a plurality of cells arranged in a matrix thereof, a connective cell, which is obtained by interrelating a predetermined plurality of cells with one another, is displayed. Further, a normal numerical clue, which is caused to correspond to a row and a column in the matrix and represents the number of cells to be marked in the corresponding row and column, is displayed. Still further, a large numerical clue, which represents the number of cells to be marked in a contiguous form over a plurality of adjoining rows or a plurality of adjoining columns, is displayed so as to range over the plurality of rows or the plurality of columns. In accordance with an operation performed by a player, specific cells are marked, and then whether or not a set of the marked cells presents a figure which is a solution of a puzzle having been previously set.