Number Maze
by Sol Guber
Number Maze is a joystick game of calculation and speed. But instead of rooms and walls, you must find an open path through a maze of numbers using mathematical rules.
In each of sixteen rows are twelve numbers. The object of the game is to move the flickering cursor from the upper lefthand corner to the highlighted number in the bottom row. The cursor moves to another number, only if the move follows one of the mathematical rules for adding, subtracting, multiplying or dividing by a factor. As the cursor moves, the numbers are highlighted, while a clock in the lower right corner records your elapsed time.
You can restart if you wish; or, if you really get frustrated, the computer will show you the solution and you can begin a new game. Fig. 1 shows you a typical maze. Its factors are + 1, + 2,  1,  2.
Your answers to a series of questions at the beginning of each game make the maze easier or harder. The first question asks if you wish to use your own number factors for the mathematics problems in the maze. Factors must be greater than zero and less than ten. If you wish, the computer will select random numbers between one and nine.
The second question asks if you want to use multiplication and division factors. The third question asks if the maze is to be one way. In a oneway maze, you cannot go back to a previous position, unless the factoring rules allow it. A oneway maze is very hard.
If you wish to use your own factors, the computer asks first for the addition factors, then for the subtraction factors, and finally for the multiplication and division factors. When you enter your own factors, the computer will not ask about a oneway maze.
If you type a letter in answer to a question, or your answer is not allowed, the questions start over. If you use your own factors, then you can use the same number twice. The higher the numbers used for the factors, the more difficult the maze game. For the easiest maze, use small numbers like one and two, and make the maze two way so that there is a return path.
Example of Play
Let me explain the game using addition and subtraction rules as follows: + 4, + 5,  2 and  5. Suppose that a position square contains the number 45. The legal moves are to a position containing one of these numbers: 49 (+ 4), 50 (+ 5), 43 ( 2), or 40 (  5). If the surrounding positions do not contain one of these numbers, then you have lost your way in the maze. If a surrounding position contains the number 50, then you can move the joystick in that direction. The number 50 becomes highlighted.
Your next possible move is to a position containing either 54 (+ 4), 55 ( + 5), 48 (  2), 45 (  5). Again, if the position above or below or to the sides of your present position does not contain one of these numbers, then you are lost in the maze.
You can move the joystick horizontally or vertically, but not diagonally. And you can't score in this game; you can only beat your previous time.
In oneway mazes, you can become stuck. Sometimes you can't make any legal moves. If you don't move for about 30 seconds, then the computer starts asking questions on the bottom of the screen. The first question asks if you need any help. A "Y" or "N" will be highlighted and the cursor moves from one to the other. Use your joystick to answer the questions. Press the trigger when your answer is highlighted. If you answer N to the help question, then the maze continues with no clock change. If you answer Y, then the computer redraws the maze and the cursor returns to the upper left corner. The clock is put back to zero.
If you answer N, then the computer asks if you want the solution. If so, the computer gives you the solution. If you didn't want the solution then the questions start over. You can start a new game after the computer reveals the solution.
To make the puzzle easier, try creating a twoway maze. To do this, make the subtraction factors the opposite of the addition factors and make the multiplication factors the inverse of the division factors. Now you can move through the maze backwards.
If you design a oneway maze, your moves must be well thought out to be sure that you are on the correct path. The higher the factors, the more difficult the maze.
The computer can generate a very complicated maze by using all four types of factorsadditions, subtraction, multiplication and division. Since all the numbers must be less than 100, the multiplication and division factors are used less often than the addition and subtraction factors.
If you make an error while entering your own factors, you can enter a letter rather than a number. This causes the questions to repeat, and you can correct your entries.
Sol Guber is an engineer who has been programming his Atari for about two years. He's taught both beginning and advanced Basic classes.

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