虫友们，python循环，希望有结果

C = 50
F = 0
print("摄氏温度    华氏温度")
while C <= 100:
    F = C * 9 / 5 + 32
    print("%4d %10d"%(C , F))
    C += 5

str = raw_input("请输入数值，用空格隔开:")
lst1 = str.split(" ")
i = 0
sum=0
for  i in range(len(lst1)):
    num=int(lst1[i])
    if num==-1:
        break
    sum=sum+num
    i += 1
print("平均数=%.2f"%(sum/i))

题目解答如下（如有帮助，请点击这个回答的采纳按钮）：

#4
x=int(input('x:'))
summary=sum([(-1)**(i-1)*x/i for i in range(1,4)])
print(summary)
#5
for f in range(50,101,5):
    c=(f-32)*5/9
    print(f'华氏{f}->摄氏{c:.2f}')
#6
scores=[]
while True:
    inp=input()
    if inp=='-1':
        break
    scores.append(int(inp))
print(f'平均成绩为{sum(scores)/len(scores):.2f}')