1. In the computer, due to hardware constraints, the data has a length limit, so the data exceeding the length in the computer will be discarded.
2. As shown in the figure below, signed and unsigned numbers
3. Several important units of measurement
Byte 1Byte = 8Bit
Word 1Word =16Bit
Double word 1DWord = 32Bit
4. Logical operations
(Tucao: This is the first question of the introductory exam. During the exam, I thought that as long as this thing does not make mistakes, no matter how low the score is, it will not be uncomfortable.
As a result, I went out of the examination room and saw that I underestimated it, and I can’t say I underestimated it, but I still didn’t learn it by myself.)
In fact, the essence of the circuit diagram in the figure below is already very clear.
（1）或（or |）
(2) with (and &)
(3) Exclusive OR (xor^)
(4) Non (not!)
It can only be said that this is really simple, if 0 is 1, if 1 is 0
5. How does the CPU operate?
For example, counting 5+4=?
Just look at the picture here, the person who designed this algorithm is really, really a genius
6. About Simple Encryption
The main thing is to use XOR algorithm for encryption