如何成功关闭此代码中的 While 循环？它似乎不承认我的休息条件？

Question

问题提示如下：

创建交互式学生记录系统。
提示用户输入学生姓名。
然后提示用户输入数字等级
重复此操作，直到用户输入“完成”来代替名称。
然后打印每个学生和他们的平均成绩

我想出了以下代码（我是初学者，如果这很明显很抱歉）

# I am creating a dictionary so I can store multiple values that are associated with one name
lst = []
dict = {}

while True:
  try:
    name = str(input("Please enter student's name."))
    grade = int(input("Please enter grade student recieved."))
    
    if (name not in list(dict.keys()) and name != "done"):
      lsst = []
      lsst.append(grade)
      dict[name] = lsst
      print(lsst)
      continue

      
    
    elif name in list(dict.keys()):
      lsst.append(grade)
      print(lsst)
      continue
    
    elif name == "done":
      break
  
  except ValueError:
    print("Try Again")
    pass

for i in range(list(dict.keys())):
  print(f"{name}: {grade}")

我在输入姓名输入“完成”后尝试打印平均值，但它只是继续进行下一个输入查询。为什么会这样，我该如何解决？

Answer 1

代码中有很多错误，但我会在更正的版本中分解它们。

names_and_grades = {} # I renamed this variable because there is a built in type called dict in Python.

while True: # Using while True is usually discouraged but in this case, it's hard to avoid that.
    try:
        name = input("Please enter student's name.") # No need to convert to string as it takes the input as a string by default.

        if name == "done": # After you prompted for a name immediately check whether the user entered done. This way, you can break right after that.
            break

        grade = int(input("Please enter grade student recieved."))

        if name not in names_and_grades.keys():
            names_and_grades[name] = [grade] # We don't actually need a separate list as the entry in the dictionary will be the list itself (that's why it's put between brackets).
        elif name in names_and_grades.keys():
            names_and_grades[name].append(grade) # Once the list was declared, you can simply append it.

        print(names_and_grades[name]) # No need to repeat this twice in the if-else statements, you can just write it after them. And a very important thing, there is no need to use continue, since you are using if-elfe. When you are using if-else, only one of the blocks will be used, the first block where the condition evaluates as true.

    except ValueError:
        print("Try Again")

for k in names_and_grades.keys():
    print(f"{k}: {names_and_grades[k]}") # This is the simplest way to iterate through a dictionary (if you want to format the entries), by iterating through the keys of the dictionary and with the help of the keys, calling the appropriate values.

我希望这会有所帮助，如果有不清楚的地方请告诉我。

Answer 2

@I8ACooky - 有一些逻辑和语法错误，所以我建议你运行它，看看你是否能得到一些想法来解决你自己的问题：

from collections import defaultdict


grades = defaultdict(list)   # in case for multiple scores for a student
print('Welcome to the simple Scoring program. ')

while True:
    
    try:
        
        name = input("Please enter student's name.")
        score = int(input("Please enter grade student recieved: "))

        if name == 'done' and score == 0:
            break
        
        grades[name].append(score)

    except ValueError:
        print('Try Again....?')
      
print(dict(grades))

#------------------------
# average scores leave as an exercise...

输出：

Welcome to the simple Scoring program. 
Please enter student's name.Adam
Please enter grade student recieved: 100
Please enter student's name.Bob
Please enter grade student recieved: 60
Please enter student's name.Cindy
Please enter grade student recieved: 80
Please enter student's name.Adam
Please enter grade student recieved: 80
Please enter student's name.Bob
Please enter grade student recieved: 100
Please enter student's name.Cindy
Please enter grade student recieved: 90
Please enter student's name.done
Please enter grade student recieved: 0
{'Adam': [100, 80], 'Bob': [60, 100], 'Cindy': [80, 90]}