print("有一个已经排好序的列表。现输入一个数，要求按原来的规律将它插入列表中")
a = [1,3,5,7,9]
insert_num = int(input("请输入插入的数字："))
if insert_num <= a[0]:
a.insert(0,insert_num)
elif insert_num >= a[len(a)-1]:
a.insert(len(a) ,insert_num)
else:
for i in range(len(a)):
if insert_num > a[i] and insert_num <= a[i+1]:
a.insert(i+1,insert_num)
break
print(a)
