Python algorithm practice week1- fundamentals of programming

0x00 machine language 、 Assembly language and high-level language ( With 2+3 For example )

• machine language ：01 Code 、CPU Cognitive language
  • Add operation ：1001
  • Subtraction operation ：1010
  • 2+3：1001 0010 0011
• assembly language ： Human readable mnemonics have been added to machine language
  • Add operation ：ADD
  • Subtraction operation ：SUB
  • 2+3：ADD 2,3
• High-level language ： A language close to natural language
  • sum = 2 + 3

0x01 How programming languages work

• A compiled
  • Convert high-level language source code into object code （ machine language ）
  • The program can run directly
  • The execution speed of the object code is fast
  • Representative language ：C/C++
• interpreted
  • Convert high-level language source code into object code one by one , Executing while converting
  • Each time you run a program, you need source code and an interpreter
  • It has good cross platform portability
  • Representative language ：Java、Python

0x02 Program flow chart

Use a specified series of figures 、 Flow line and text explain the basic flow and control flow in the algorithm .

The basic elements of the flowchart include

• A box representing the corresponding operation
• Flow lines with arrows
• Necessary text inside and outside the box

Sequential structure

• The Fahrenheit temperature is described by a sequential structure F Convert to Celsius C The process of
• The formula ：C = 5/9*(F-32)
• algorithm flow chart

Python Code implementation

Branching structure

• Find the absolute value of a given number
• algorithm flow chart

• Python Language implementation

# Branching structure , Find the absolute value
R = int(input(' Please enter a number R:'))
if(R >= 0):
print('R The absolute value of is {}'.format(R))
else:
print('R The absolute value of is {}'.format(-R))

Loop structure

• Input n Value , seek 1 To n Continuous addition and
• algorithm flow chart

Python Language implementation