20191218 "Introduction to Information Security" fifth weekly summary

Learning content summary

This week learning a computer language from lower to higher: Machine Language (expressed in binary), assembly language (joined mnemonic) as well as high-level language (more readable), to understand the virtual machine Pep / 8 operating principle, and use Pep / 8 completed a simple machine code and assembly language programming, more deeply understand the principles of operation of the computer system; know the importance of the pseudo-code in the programming, and to understand the pseudo code does not stick to the form, but to articulate objectives and implementation process; also learned the importance of manual simulation program while debugging the program: when the value of boundary value problems, may wish to bring a few simple data before running the program before you begin operating the computer simulation will see What is the result appears; understanding the branch structure and the loop structure.

Textbook learning and problem-solving process

"Self is the craft" Section 3 of Chapter 11, for example with regard to the lambda Python's official documentation is somewhat difficult to understand:

By looking for information, hands-on simulation to modify the program, etc., I found the first part of a list of variable names can refer to the entire generation of variables, such as the above figure can be used pair instead of pairs, in fact, can also be used in place of p pairs; secondly under lambda expressions in this case returns the ordered list of elements i + 1 according to a first element (tuple index) value is sorted by size as illustrated in the second element; third, if pair [. 1] into other values, such as pair [0] or the pair [-1] and what will happen? Through debugging, I found that if the index value is greater than a given number of elements to -1, the index value is less than 0 it back into the range of values (the range of a few elements have index values belong to a few dollars domain).

Code debugging and problem solving in the process

By learning Switch statement, I found great advantages relative if statements variety of circumstances: the condition is not easy to overlapping cross, simple sentence structure is not jumbled, readable.