北京大學ACM題
Here is a geometric problem. You have an angle and some squares in the first quadrant of the plane rectangular coordinates. The vertex of the angle is fixed on the origin O of the coordinates, and both of its radial lines are specified by the input. The sizes of the squares are also specified by the input, and the squares can shift vertically and horizontally. Now your job is to use the squares and the radial lines of the angle to enclose the maximum area, which excludes the area of the squares (see Figure 1). You should note that the edges of the squares must be parallel to the axes.
北京大學ACM比賽題
The game of Scrabble is played with tiles. A tile either has a single letter written on it, or it is blank. In the latter case, the tile may be used to represent a letter of your choice. On your turn, you arrange the tiles to form a word. Each tile may be used at most once, but not all tiles need to be used. Given several Scrabble tiles and a dictionary, determine how many words in the dictionary can be formed using the given Scrabble tiles.
