递归函数

例子：

def my_sum1(n):
    if n<=0:
        return 0
    else:
        return my_sum1(n-1)+n
# res = my_sum1(10)
# print(res)

lst = []
def my_sum2(n):
    if n==1:
        return 1
    else:
        return my_sum2(n-1)+2
# res = my_sum2(3)
# print(res)

for i in range(1,11):
    lst.append(my_sum2(i))
print(lst)
print(sum(lst))

def my_sum(n):
    sum = 0
    for i in range(n):

        sum += i