Decision Statements

Before learning this part, I was not proficient in the various if statements. Through the exercises in this part, I learned how to effectively use if`, elif and else to handle different logical situations. I also mastered how to combine logical operators to make more complex judgments, such as judging the positive and negative and parity of a number. In addition, I also realized that conditional statements can make the behavior of the program more flexible and intelligent.

In the process of learning if statements, I deeply understood the various uses of conditional judgments by building a student performance evaluation system, temperature and size comparison codes. Initially, I was confused about how to handle multiple conditions, but I gradually grasped the logic of this structure using if and elif and else-if in the implementation to output the corresponding rank based on the score. Through this practice, my understanding of if statements improved significantly and I was able to confidently apply this knowledge in my projects.

When learning Python syntax, I was not very sensitive to identifying syntax errors, especially missing `if` or colon `:` in conditional statements. At first, I often forgot to add a colon after the conditional statement when writing code, which caused the code to fail to run and I could not clearly find the error. Through this study, I not only learned the rule that a colon must be added after each `if`, `elif`, and `else` statement, but also learned how to check the code carefully to ensure the correctness of the syntax. This made me more confident when writing and debugging code, and I was able to find and correct errors faster, which improved my programming ability.

First of all, the use of colon : is the basis of decision-making statements. A colon must be added after each if, elif, and else statement so that Python can correctly identify the next code block. This is what we repeatedly emphasize during the learning process, and any omission will lead to syntax errors. In addition, it is equally important to maintain a consistent indentation style (usually four spaces) in loop structures. Indentation is used in Python to clarify the beginning and end of code blocks, which helps to improve the readability and logical clarity of the code. This is like the essay we write. At the beginning of each paragraph, we need to indent to better distinguish different paragraphs.

Another important aspect is the application of logical operators. We often use coordinating conjunctions (such as and and or) in our daily lives. These operators are also used in code and are very practical when building complex conditions. Flexible use of them can effectively handle multiple scenarios in one if statement, reduce code duplication, and improve the intelligence of the program. By combining this knowledge, we can use decision-making statements more flexibly in programming practice, thereby improving the quality of code.

Among the learning objectives for this unit, I think I need to pay special attention to "How to use nested if statements." Although I have mastered the basics of if and elif usage, nested if statements sometimes confuse me when dealing with complex logic, especially when it comes to understanding the hierarchy and indentation of code.

To solve this problem, I plan to deepen the understanding by writing more sample code containing nested if statements. Specifically, I can start from actual scenarios, such as writing a simple user input validation program to check the age and score entered by the user, and give corresponding feedback based on different conditions. Through this practice, I was able to better understand how nested structures work and grasp the flow of logic under complex conditions.

In a previous assignment, I was deducted a point because I did not use the nested if statement required by the teacher. This taught me a lesson. By practicing and reflecting on the concepts above, I believe I can make significant progress in my use of nested if statements, thereby improving my programming and problem-solving skills.