tut.wrld

: (c) P. Langston, 1978
#1      What would the binary number for six be?
"Logical bit operations use binary numbers -- that's numbers with only
ones and zeroes.  The numbers that we usually use are called \"decimal\"
and use the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.
You can see that binary stuff should be easier than decimal -- and it is!

    Decimal  Binary
       1        1     These columns of numbers are the same,
       2       10     just expressed in two different ways.
       3       11
       4      100
       5      101
The next DECIMAL number is \"6\", what would the next BINARY number be?"
	6          v+1.1   m="No, that's the DECIMAL number for six."
	110     2  m="Right on!\n"
	hint       m=\
"If you add 1 + 2 you get 3, in binary that's 1 + 10 = 11
Try 2 + 4 = 6 in binary..."
	uncle   2  v+2.1   m=\
"The answer is 110 -- Notice that 100 (4) + 10 (2) = 110 (6) !\n"

#2      What does 1 & 1 equal?
"Now you're going to learn about the AND operation.
The symbol used for AND is \"&\".  The logical AND is usually diagrammed as:
\           0   |   1   |        This means that
\        +------+-------+        0 & 0 = 0
\     0  |  0   |   0   |        0 & 1 = 0,
\   -----+------+-------+        1 & 0 = 0,
\     1  |  0   |   1   |        etc.
\   -----+------+-------+
What would 1 & 1 be?"
	0          v+1.1   m="No, but you're close..."
	1       3  m="You got it!\n"
	2          v+1.1   m=\
"No, that's the answer for 1 + 1.
Notice that the AND operation is very similar to multiplication,
except there are no \"carries\"."
	hint       m=\
"ANDing binary digits together is just like multiplying them..."
	uncle   3  v+2.1   m=\
"The answer is 1.  If you look in the square that's under the 1 on top
and to the right of the 1 on the left you'll see a 1.
That means that 1 & 1 = 1.\n"

#3      What does 110 & 101 equal?
Okay, now you're ready to learn about ANDing bigger numbers.
\ \ \ 01 & 11 = 01
If you ANDed together 01 and 11 you would get 01 because
the first bit of 01 is ANDed with the first bit of 11, (0 & 1 = 0);
and the second bit of 01 is ANDed with the second bit of 11, (1 & 1 = 1).
What would you get if you ANDed together 110 and 101?
	100     4  m="Great!  You got it.\n"
	110        v+1.1   m="No, the second bit is wrong."
	101        v+1.1   m="Nope, the third bit is wrong."
	hint       m=\
"Think of it as three little problems. 1 & 1 = ?  1 & 0 = ?  and 0 & 1 = ?
Then take the three answers and run them together."
	uncle   4  v+2.1   m=\
"The answer is 100.  Think of it as:
  1 1 0
& 1 0 1
-------
  1 0 0"

#4      What does 1 | 0 equal?
"Now let's look at logical OR (symbol is \"|\").
Here's the diagram for logical OR:
\           0   |   1   |
\        +------+-------+
\    0   |  0   |   1   |
\  ------+------+-------+
\     1  |  1   |   1   |
\  ------+------+-------+
What does 1 | 0 = ? "
	1       5  m="Nice going!\n"
	0          v+1.1   m="You had a 50/50 chance and you blew it!"
	hint       m=\
"Look at the square under the 1 and on the line with the 0 at the left."
	uncle   5  v+2.1   m=\
"The answer is 1.  When you're ORing two 1 bit numbers together the answer
will be 1 unless the two bits are BOTH 0 (upper left corner of the diagram)."

#5      What does 1010 | 1100 equal?
Let's try ORing some bigger numbers.  Remember that you treat each bit position
separately to get the answer.
What does 1010 | 1100 equal?
	1010       v+1.1   m="No, the second bit should be = 0 | 1"
	1100       v+1.1   m="The third bit should be = 1 | 0"
	1110    6  m="Yup, that's it!"
	hint       m=\
"Think of it as:
  1 0 1 0
| 1 1 0 0
---------
  ? ? ? ?"
	uncle   6  v+1.2   m="The answer is 1110\n"

#6      Do you want to know how well you did?
You're all done for today.  That was easy, huh?  (and FUN, too!)
Do you want to know how well you did?
	yes  -2  v>2.3   m="You did terrible!  You gave up on %2% questions."
	yes  -2  v>2.1   m="You did so-so, but you gave up on %2% questions."
	yes  -2  v>2.0   m="You gave up on one and got %1% wrong."
	yes  -2  v<1.1   m="You got a perfect score!"
	yes  -2  v<1.5   m=\
"You got only %1% wrong -- that means you probably learned something!"
	yes  -2  m=\
"You got %1% wrong; you probably ought to try this again sometime..."
	no   -2  m="Okay, be that way..."
	hint     m="Type yes (of course)."
	*        ...   m="Please answer the question."