条件判断及循环

age = 9
if age >= 18:
    print('teenager')
elif age >= 6:
    print('adult')
else:
    print('kid')

若x是非零值、非空字符串、非空List等，就判为True

s = input("birth:")
birth = int(s)
if birth < 200:
    print('00前')
else:
    print('00后')

input()反回str类型，用int(s)强制类型转换

names = ['Michael','Bob','Tracy']
for name in names:
    print(name)
sum = 0
for x in list(range(101)):
    sum = sum + x
print(sum)