for i in range(10):
        print(i)

2、打印偶數：

for i in range(0,10,2):
        print(i)

3、if判斷中猜遊戲，升級(只能猜三次，超過三次沒猜對，提示退出)

_age = 18

for i in range(3):
    guess_age = int(input("guess_age:"))
    if guess_age == _age:
        print("GoodLuck!")
        break
    elif guess_age > _age:
        print("cai da le ")
    else:
        print("cai xiao le ")
else:
    print("chao guo san ci qing tui chu!!!")
 

python中for循環