day9-作业

day9-作业

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1. 编写函数，求1+2+3+…N的和

def y_sum(num: int):
    sum1 = 0
    for x in range(1, num+1):
        sum1 += x
    return sum1
# print(y_sum(100))

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2. 编写一个函数，求多个数中的最大值

def y_max(*args):
    if not args:
        return
    max1 = args[0]
    for item in args:
        if item > max1:
            max1 = item
    return max1
# print(y_max(10, 30, 80, -10, -50, 56))

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3. 编写一个函数，实现摇骰子的功能，打印N个骰子的点数和

import random

def dice(n: int):
    sum1 = 0
    for x in range(n):
        num1 = random.randint(1, 6)
        sum1 += num1
    return sum1
# print(dice(5))

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4. 编写一个函数，交换指定字典的key和value。

def exchange(dict1: dict):
    dict2 = dict1.copy()
    dict1.clear()
    for x in dict2:
        dict1[dict2[x]] = x
    return dict1
# print(exchange({'a': 1, 'b': 2, 'c': 3}))

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5. 编写一个函数，提取指定字符串中所有的字母，然后拼接在一起产生一个新的字符串

def alpha(str1: str):
    str2 = ''
    for x in str1:
        if 'A' <= x <= 'Z' or 'a' <= x <= 'z':
            str2 += x
    print(str2)
# alpha('a123sA+12gf')

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6. 写一个函数，求多个数的平均值

def avg(*args):
    length = len(args)
    avg1 = sum(args) / length
    return avg1
# print(avg(19, 212, 345, 86, 99))

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7. 写一个函数，默认求10的阶乘，也可以求其他数字的阶乘

def factorial(num=10):
    fact = 1
    for item in range(1, num+1):
        fact *= item
    return fact
# print(factorial())

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以下题目请自己造轮子

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8. 写一个自己的capitalize函数，能够将指定字符串的首字母变成大写字母

def caps(str1: str):
    if not str1:
        return str1
    ch = str1[0]
    if 'a' <= ch <= 'z':
        ch = chr(ord(ch[0])-32)
    return ch+str1[1:]
# print(caps('1fc'))

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9. 写一个自己的endswith函数，判断一个字符串是否已指定的字符串结束

def ends(str1: str, str2: str):
    length = len(str2)
    if str1[-length:] == str2:
        return True
    return False
# print(ends('asewr3d12d', '2d'))

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10. 写一个自己的isdigit函数，判断一个字符串是否是纯数字字符串

def is_num(str1: str):
    for item in str1:
        if not ('0' <= item <= '9'):
            return False
    return True
# print(is_num('234243'))

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11. 写一个自己的upper函数，将一个字符串中所有的小写字母变成大写字母

def big(str1: str):
    str2 = ''
    for item in str1:
        if 'a' <= item <= 'z':
            str3 = chr(ord(item)-32)
            str2 += str3
        else:
            str2 += item
    return str2
# print(big('a232Aa2sdf'))

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12. 写一个自己的rjust函数，创建一个字符串的长度是指定长度，原字符串在新字符串中右对齐，剩下的部分用指定的字符填充

def y_rjust(str1: str, num: int, str2: str):
    str3 = ''
    length = len(str1)
    if length >= num:
        return str1
    else:
        str3 += (str2 * (num-length))
        str1 = str3 + str1
        return str1
# print(y_rjust('abcd', 7, '='))

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13. 写一个自己的index函数，统计指定列表中指定元素的所有下标，如果列表中没有指定元素返回-1

def y_index(list1: list, value):
    count = 0
    for x in range(len(list1)):
        if list1[x] == value:
            print(x, end=' ')
            count += 1
    if count == 0:
        print(-1)
# y_index([1, 2, 3, 1, 5, 6, 1], 1)

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14. 写一个自己的len函数，统计指定序列中元素的个数

def y_len(nums):
    count = 0
    for _ in nums:
        count += 1
    return count
# print(y_len((1, 34, 'a', 45, 'aaa')))

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15. 写一个自己的max函数，获取指定序列中元素的最大值。如果序列是字典，取字典值的最大值

def yxy_max(array):
    if type(array) == dict:
        key1 = list(array)
        max1 = array[key1[0]]
        for key in array:
            if array[key] > max1:
                max1 = array[key]
    else:
        max1 = array[0]
        for item in array:
            if item > max1:
                max1 = item
    return max1
# print(yxy_max({'a': 12, 'b': 23, 'c': 345}))

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16. 写一个函数实现自己in操作，判断指定序列中，指定的元素是否存在

def y_in(array, value):
    for item in array:
        if item == value:
            return True
    return False
# print(y_in((12, 90, 'abc', '100'), 90))

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17. 写一个自己的replace函数，将指定字符串中指定的旧字符串转换成指定的新字符串

def y_replace(str1: str, str2: str, str3: str):
    length = len(str2)
    length1 = len(str1)
    for x in range(length1-length+1):
        if str1[x:x+length] == str2:
            str1 = str1[:x] + str3 + str1[x+length:]
    return str1
# print(y_replace('how are you?and you?', 'you', 'me'))

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18. 写四个函数，分别实现求两个列表的交集、并集、差集、对称差集的功能

# 并集
def union(list1: list, list2: list):
    for item in list2:
        if item not in list1:
            list1.append(item)
    return list1
# print(union([1, 2, 3, 4], [3, 4, 5, 6]))

# 交集
def mix(list1: list, list2: list):
    list3 = []
    for item in list1:
        if item in list2 and item not in list3:
            list3.append(item)
    return list3
# print(mix([1, 2, 3, 4, 3], [3, 4, 5, 6]))

# 差集
def diff(list1: list, list2: list):
    list3 = []
    for item in list1:
        if item not in list2:
            list3.append(item)
# diff([1, 2, 3, 4], [4, 3, 4, 5, 6])

# 补集
def complementary(list1: list, list2: list):
    list3 = []
    for item in list1:
        if item not in list2:
            list3.append(item)
    for item in list2:
        if item not in list1:
            list3.append(item)
    return list3
# print(complementary([1, 2, 3, 4], [4, 3, 4, 5, 6]))

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