目录
一.斐波拉契数列
# 两个元素的总和确定了下一个数
#关键字end可以用于将结果输出到同一行,或者在输出的末尾添加不同的字符
a,b = 0,1
while b <100:
print(b,end=',')
a,b=b,a+b
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二.计算 30 以内可以被 3 整除的整数:
multiples = [i for i in range(30) if i % 3 == 0]
print(multiples)
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三.集合推导式
zlw={i**2 for i in (1,2,3)}
print(zlw)
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四.判断不是 abc 的字母并输出:
>>> a = {x for x in 'abracadabra' if x not in 'abc'}
>>> a
{'d', 'r'}
>>> type(a)
<class 'set'>
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五.简单的if语句
zlw = 100
if zlw:
print('zlw love zxs')
print(zlw)
zxs = 10
if zxs:
print('zxs love zlw too')
print(zxs)
print('love each other')
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?六.狗狗年龄演算
age = int(input('输入狗狗的年龄:'))
print('')
if age <=1:
print('你在开玩笑吧')
elif age == 1:
print('狗狗年龄相当于14岁的人')
elif age == 2:
print('狗狗年龄相当于22岁的人')
elif age > 2:
human = 22+(age-2)*5
print('相对于的人类的年龄',human)
input('点击enter键退出')
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?七.猜数小游戏
number = 8
guess = 1
print("开始猜字谜吧")
while guess != number:
guess=int(input("请输入你的数字:"))
if number == guess :
print("恭喜你猜对了")
elif guess < number:
print("数字偏小,继续猜吧!")
elif guess > number:
print("数字偏大,继续猜吧")
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?八.if的嵌套
num = int(input('输出一个数字:'))
if num %3 ==0:
if num %2 ==0:
print('这个数字可以整除2和3')
else:
print('只能整除3,不能整除2')
else :
if num %3 ==0:
print('这个数字只能整除3')
else:
print('只能整除3,不能同时整除')
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九.循环语句:1到100的和
n = 100
sum = 0
counter = 1
while counter <= n:
sum = sum + counter
counter +=1
print('1到%d的数为%d'%(n,sum))
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十.无限循环
zlw = 100
while zlw == 100: # 结果永远为true
num=int(input("输入你的数字:"))
print("你的数字为:",num)
print("GOOD BYE")
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?十一.while 循环使用 else:
count = 0
while count <10:
print(count,'小于10')
count = count + 2
else:
print(count,'大于或者等于10')
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十二.for循环
以下 for 实例中使用了 break 语句,break 语句用于跳出当前循环体:
names = ("zlw","lmc","zxs","csl","zgj")
for name in names:
if name == "zxs":
print("我不爱你!")
break
print("我爱你!" + name)
else:
print("没有循环结构!")
print("完成循环!")
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执行脚本后,在循环到 "zxs"时会跳出循环体:
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?十三.range函数
如果你需要遍历数字序列,可以使用内置range()函数。它会生成数列,例如:
for i in range(10):
print(i)
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也可以使range以指定数字开始并指定不同的增量(甚至可以是负数,有时这也叫做'步长'):?
for i in range(0,10,3):
print(i)
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?您可以结合range()和len()函数以遍历一个序列的索引,如下所示:
a = ("zlw","zxs","lmc","csl","lj")
for i in range (len(a)):
print(i,a[i])
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十四.break 和 continue 语句及循环中的 else 子句?
break 执行流程图:
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continue 执行流程图
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while 语句代码执行过程:
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for 语句代码执行过程:
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break?语句可以跳出 for 和 while 的循环体。如果你从 for 或 while 循环中终止,任何对应的循环 else 块将不执行。
continue?语句被用来告诉 Python 跳过当前循环块中的剩余语句,然后继续进行下一轮循环。
while中使用break:
n = 5
while n > 0:
n -= 1
if n == 2:
break
print(n)
print('循环结束')
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?while中使用continue:
n = 5
while n > 0:
n -= 1
if n == 2:
continue
print(n)
print('循环结束')
(虽然只是一个单词的改变,但是运行结果完全不一样)
?以下实例循环字符串 Runoob,碰到字母 o 跳过输出:
for letter in 'Runoob': # 第一个实例
if letter == 'o': # 字母为 o 时跳过输出
continue
print ('当前字母 :', letter)
var = 10 # 第二个实例
while var > 0:
var = var -1
if var == 5: # 变量为 5 时跳过输出
continue
print ('当前变量值 :', var)
print ("Good bye!")
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循环语句可以有 else 子句,它在穷尽列表(以for循环)或条件变为 false (以while循环)导致循环终止时被执行,但循环被 break 终止时不执行。
如下实例用于查询质数的循环例子:
for n in range(2, 10):
for x in range(2, n):
if n % x == 0:
print(n, '等于', x, '*', n//x)
break
else:
# 循环中没有找到元素
print(n, ' 是质数')
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十五.pass?
for letter in 'Runoob':
if letter == 'o':
pass
print ('执行 pass 块')
print ('当前字母 :', letter)
print ("Good bye!")
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(未完待续~)
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