python基础知识点

'''


name = '张三'
age = '18'
edu = '清华大学'
x1 = f'年龄为{age}的{name}考上了{edu}'
print(x1)


x = int(input('请输入一个整数：'))
if x % 2 == 0:
    if x % 10 == 0:
        print(f'{x}既能被2整除又能被10整除')
    else:
        print(f'{x}既能被2整除但是不能被10整除')
else:
    print(f'{x}既不能被2整除又不能被10整除')


year = int(input('请输入一个整数年份：'))
result = f'{year}是闰年'if (year % 4 == 0 and year % 100 != 0) or (year % 400 == 0) else f'{year}是平年'
print(result)

if year % 400 == 0:
    print(f'{year}是闰年')
elif year % 4 == 0 and year % 100 != 0:
    print(f'{year}是闰年')
else:
    print(f'{year}不是闰年')


if (year % 400 == 0) or (year % 4 == 0 and year % 100 != 0):
    print(f'{year}是闰年')
else:
    print(f'{year}是平年')
'''
'''

#index的用法
list1 = [1,2,6,3,7,9,4,5,0]

print(list1.index(4))
print(len(list1))


#冒泡排序
list2 = [1, 200, 39, 77, 99, 33, 78, 28, 7, 556]
for i in range(0, len(list2)):
    for j in range(0, len(list2) - 1):
        if list2[j] > list2[j + 1]:
            list2[j], list2[j+1] = list2[j+1], list2[j]
print(f'冒泡排序的最终结果是：{list2}')
'''
'''

list3 = []
list3.append('小明:18 ')
print(list3)

str1 = '123\nabc'
print(str1)
str2 = '123\tabc'
print(str2)
str3 = '123\'abc'
print(str3)
str4 = r'123\nabc'
print(str4)
'''
'''

str4 = '我是凯，我最喜欢打小鲁班，哈哈哈，来受死吧，小鲁班。'
print(str4.rindex('我'))
print(str4.find('我'))

str1 = '11233'
print(str1.isdigit())
str2 = 'acfsf...'
print(str2.isalpha())
print(str2.isalnum())
str3 = 'HHGGYUHUH'
str4 = 'hhhorogj'
print(str3.lower())
print(str4.upper())
str5 = 'hello, world'
print(str5.title())
print(str5.capitalize())
'''
'''
#正确的空集合创建方法
set1 = set()
print(type(set1), set1)
#集合的构造器语法
str1 = 'hello,world'
set2 = set(str1)
print(set2)

str3 = [1,2,3,4,5,6]
set3 = set(str3)
print(set3)

#集合的遍历
for i in set3:
    print(i)

#集合的增
str4 = '12134, java'
set4 = set(str4)
set4.add('python')
print(set4)
set4.update('c++','java')
print(set4)
set4.pop()
print(set4)
set4.clear()
print(set4)
'''
'''

list1 = ['张三','张三','李四','王五','王五','李四']
result = []
for i in list1:
    if i not in  result:
        result.append(i)
print(result, sep='')
print('*' * 90)
list1 = ['张三','张三','李四','王五','王五','李四']
#列表转集合去掉重复元素
set2 = set(list1)
print(set2)
#再将集合转列表
list2 = list(set2)
print(list2)
'''
'''

for i in range(2, 101):
    for j in range(2, i):
        if i % j  == 0:
            break
    else:
        print(f'{i}是素数')


for n in range(100, 1000):

    i = n // 100
    j = n % 100 // 10
    k = n % 10
    if n == i ** 3 + j ** 3 + k ** 3:
        print(f'{n}是水仙花数')
'''
'''

for i in range(1,10):
    for j in range(1,10):
        for k in range(1, 10):
            if (i != j) and (i != k) and (j != k):
                print(i, j, k)
'''
'''
t1 = (12, 'abc', 'abbu')
print(type(t1))
print(len(t1))
t2 = (123,)
print(t1 + t2)
print(t1 * 4)
#元组的直接遍历
for i in t1:
    print(i)
#元组的间接遍历
for i in range(len(t1)):
    print(t1[i])
#元组的下标
print(t1[-1])

#编写一个程序，输入一串字符串，输出分别有多少个字母和数字
str1 = input('请输入一串字符串：')
nums = 0
letters = 0
for i in str1:
    if 'a' <= i <= 'z' or 'A' <= i <= 'Z':
        letters += 1
    elif '1' <= i <= '9':
        nums += 1
print(f'该字符串有{letters}个字母，有{nums}个数字')

#当列表有重是可以用集合去重
s1 = [1,2,3,44,5,4,2,1,3,5]
set1 = set(s1)
list1 = list(set1)
print(list1)
'''
'''

#用max来判断出现最多的次数，用content变量来保存该元素
t1 = [1, 2, 3, 4, 5, 3, 6, 7, 9, 4, 7]
#set1 = set(t1)
#print(set1)
max = 0
content = []
for i in t1:
    if max < t1.count(i):
        max = t1.count(i)
        content.clear()
        content.append(i)
    elif max == t1.count(i):
        content.append(i)
print(f'出现次数最多的数是{content}')
'''
'''

#空字典的建立
dict1 = {}
print(dict1, type(dict1))

num1 = float(input('请输入第一个数：'))
num2 = float(input('请输入第二个数：'))
sum = num1 + num2
print(f'{num1}和{num2}的和数{sum}')
num_sqrt = num1 ** 0.5
print(f'{num1}的平方根我是{num_sqrt}')
a = float(input('请输入第一个数a：'))
b = float(input('请输入第二个数b：'))
c = float(input('请输入第三个数c：'))
d = b ** 2 - 4 * a * c
C = (a + b + c) / 2
S = (C*(C-a) * (C-b) * (C - c))
print(C, S)
'''
'''
X = float(input('请输入摄氏度：'))
Y = float(input('请输入华氏度：'))
Y = (X * 1.8) + 32
X = (Y - 32) / 1.8
print(f'摄氏度转华氏度是{Y}, 华氏度转摄氏度是{X}')
'''
'''

#列表推导式
list1 = [i for i in range(101) if i % 3 == 0]
print(list1)
#字典推导式
dict_A = {'a': 101, 'b': 99, 'c': 20.1, 'd': 160}
dict_B = {i: dict_A[i] for i in dict_A if dict_A[i] > 100}
print(dict_B)
dict_C = {key : value for key, value in dict_A.items() if value > 100}
print(dict_C)

stu = [
    {'name': '小明', 'age': 18, 'score': 80, 'tel': '1234', 'sex': '男'},
    {'name': '小刚', 'age': 17, 'score': 70, 'tel': '12399', 'sex': '女'},
    {'name': '小红', 'age': 19, 'score': 90, 'tel': '1237', 'sex': '性别不明'},
    {'name': '小强', 'age': 20, 'score': 55, 'tel': '1236', 'sex': '男'},
    {'name': '小李', 'age': 15, 'score': 40, 'tel': '1235', 'sex': '女'},
    {'name': '小王', 'age': 21, 'score': 95, 'tel': '1238', 'sex': '性别不明'}
]
#统计不及格学生的个数
count = 0
for i in stu:
    #if i.get('score') < 60:
        #count += 1
    count += 1 if i.get('score') < 60 else 0
print('不及格学生个数是：', count)
#打印不及格学生的名字和成绩
for i in stu:
    if i.get('score') < 60:
        print(i['name'], i['score'])
#统计未成年学生的个数
count = 0
for i in stu:
    if i.get('age') < 18:
        count += 1
print('未成年学生的个数:', count)
#打印手机尾号是8的学生的名字
for i in stu:
    if i['tel'][-1] == '8':
        print('手机尾号是8的学生名字是:', i['name'])

#打印成绩最大的学生名字和成绩
max = 0
for i in stu:
    if max < i['score']:
        max = i['score']
        #name = i['name']
print('成绩最大学生的名字和成绩分别是：', i['name'], max)

#删除性别不明的学生
for i in range(len(stu) -1, -1, -1):
    if stu[i]['sex'] == '性别不明':
        del stu[i]
print(stu)
'''
list1 = [1, 2, 3, 3, 4, 3, 2, 1]
list2 = list1.count(3)
print(list2)

list1.sort(reverse = True)
print(list1)

def func1(x, y, z):
    print(x + y + z)

func1(20, 20, 30)