python - 对包含字符串和整数的列表中的元素求和，并将答案放入另一个列表 python

Question

我必须编写一个代码来对列表中每个学生的成绩求和并返回总和。我的代码是:

list=['student1',10,20,40,'student2',20,20,40,'student3',20,30,40,'student4',20,10,30]
list2=[]
for i in range(0,len(list1),4):
    list2.append(list1[i])
    for j in range(len(list1)):
        if j%4 == 1:
            sum= list1[j]+list1[j+1]+list1[j+2]
            list2.append(sum)
print(list2)

预期的输出应该是这样的:

['student1', 70, 'student2', 80,'student3', 90, 'student4', 60]

但我得到了这个输出:

['student1', 70, 80, 90, 60, 'student2', 70, 80, 90, 60, 'student3', 70, 80, 90, 60, 'student4', 70, 80, 90, 60]

那么我的代码有什么问题呢？

Answer 1

你可以用一个循环来完成:

lst = ['student1', 10, 20, 40, 'student2', 20, 20, 40, 'student3', 20, 30, 40, 'student4', 20, 10, 30]
result = []
for i in range(0, len(lst), 4):
    result.extend((lst[i], sum(lst[i+1:i+4])))

输出:

['student1', 70, 'student2', 80, 'student3', 90, 'student4', 60]

如果每个学生的分数不同，例如:

lst = ['student1', 10, 20, 'student2', 10, 20, 30, 'student3', 10, 20, 30, 40, 'student4', 10, 20, 30, 40, 50]

然后:

s = 0
result = [lst[0]]
for i in lst[1:]:
    try:
        s += int(i)
    except ValueError:
        result.extend((s, i))
        s = 0
result.append(s)

输出:

['student1', 30, 'student2', 60, 'student3', 100, 'student4', 150]