如何在 Python 中打印来自 while 循环和 if else 的变量答案

【问题标题】：How can I print variable which is int from while loop and if else in Python如何在 Python 中打印来自 while 循环和 if else 的变量
【发布时间】：2021-04-24 14:00:16
【问题描述】：

我从程序中得到的错误是未定义的变量。

# Python 3.9.4
# import sys
# print(sys.version)

SubjectT = input("Enter your subject: ")
Tutor_Name = input("Enter your name: ")
Iterate = int(input("How many students are there? "))
# Set counter
# create count for each student
Accumulate = 0
for i in range(Iterate):  # It will run how many time based on Iterate input
    Score = float(input("Enter score: "))
    Counter = True
    while Counter:
        if 80 <= Score < 100:
            Accumulate1 = Accumulate + 1
        elif 80 > Score >= 65:
            Accumulate2 = Accumulate + 1
        elif 65 > Score >= 50:
            Accumulate3 = Accumulate + 1
        elif Score < 50:
            Accumulate4 = Accumulate + 1
        else:
            print("The number is a negative value or incorrect")
            Again = input("Enter yes for restarting again or if you want to exit the program please press anything: ")
            if Again in ("y", "Y", "YES", "Yes", "yes"):
                continue
            else:
                break
print(f"Subject title:", {SubjectT}, "\nTutor:", {Tutor_Name})
print("Grade", "     Number of students")
print("A", "Students: ", Accumulate1)
print("B", "Students: ", Accumulate2)
print("C", "Students: ", Accumulate3)
print("D", "Students: ", Accumulate4)

这是我在 Stackoverflow 上的第一篇文章。请原谅我的任何不当内容。非常感谢。

【问题讨论】：

if-elif 语句正在声明变量，这些变量可能并不总是被执行，并且您最终希望声明所有 Accumulate 1,2,3，从而导致所述错误。

标签： python if-statement while-loop printing count

【解决方案1】：

你说

Counter = True

没有迭代，因此它将无限期地运行。使用 while 循环，您需要设置一些约束。

【讨论】：

【解决方案2】：

我意识到为什么你有 While 循环，但它仍然不能有效地为我工作 - 如果所有答案都在范围内，它永远不会终止。这应该对你有用，它对我有用。我对其进行了更改，因此每次有人输入分数时它都会检查它是否在正确的范围内，因此如果值不正确，您不必重复整个循环

SubjectT = input("Enter your subject: ")
Tutor_Name = input("Enter your name: ")
NoOfStudents = int(input("How many students are there? "))
# Set counter
# create count for each student
Accumulate = 0
Accumulate1 = 0
Accumulate2 = 0
Accumulate3 = 0
Accumulate4 = 0

def validRange(score):
    if 0 <= score <=100:
        return True
    else:
        return False
i = 1
while (i <= NoOfStudents):  # It will run how many time based on Iterate  

validInput = False
while (not validInput):
    Score = float(input("Enter score: "))
    if ( not validRange(Score)):
        print("The number is a negative value or incorrect")
    else:
        validInput = True
        if 80 <= Score < 100:
            Accumulate1 = Accumulate1 + 1
        elif 80 > Score >= 65:
            Accumulate2 = Accumulate2 + 1
        elif 65 > Score >= 50:
            Accumulate3 = Accumulate3 + 1
        elif Score < 50:
            Accumulate4 = Accumulate4 + 1
        i = i+1
    

print(f"Subject title:", {SubjectT}, "\nTutor:", {Tutor_Name})
print("Grade", "     Number of students")
print("A", "Students: ", Accumulate1)
print("B", "Students: ", Accumulate2)
print("C", "Students: ", Accumulate3)
print("D", "Students: ", Accumulate4)

【讨论】：