遍历列表中的元素并像这样更新总数:

def sum(a):
    total = 0
    index = 0
    while index < len(a):
        total = total + a[index]
        index = index + 1
    return total

你可以试试这种方法:

a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
sm = sum(a[0:len(a)]) # Sum of 'a' from 0 index to 9 index. sum(a) == sum(a[0:len(a)]
print(sm) # Python 3
print sm  # Python 2

保持简单:

def cool_sum(list: numbers):
    b = 0;
    for i in numbers:
        b += i
    return b;


a = [1, 2, 4]
print(cool_sum(a))

n = int(input("Enter the length of array: "))
list1 = []
for i in range(n):
    list1.append(int(input("Enter numbers: ")))
print("User inputs are", list1)

list2 = []
for j in range(0, n-1):
    list2.append((list1[j]+list1[j+1])/2)
print("result = ", list2)

尝试使用列表理解。喜欢的东西:

new_list = [(old_list[i] + old_list[i+1])/2 for i in range(len(old_list-1))]

我使用一个while循环来得到结果:

i = 0
while i < len(a)-1:
   result = (a[i]+a[i+1])/2
   print result
   i +=1