作业_Day8

1. 编写一个函数，求1+2+3+...+N

def sum_n(n):
    sum1 = 0
    for i in range(1,n+1):
        sum1 += i
    print(sum1)

sum_n(20)

2. 编写一个函数，求多个数中的最大值

def max_n(*nums):
    max1 = 0
    for num in nums:
        if num > max1:
            max1 = num
    print(max1)

max_n(100,88,108,45,-12)

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):
    sum1 = 0
    for x in range(0,n):
        num3 = random.randint(1,6)
        sum1 += num3
        print(num3)
    return sum1

print(dice(3))

4. 编写一个函数，交换指定字典的key和value。
   如:{'a':1, 'b':2, 'c':3} ---> {1:'a', 2:'b', 3:'c'}

dict1 = {'a':1,'b':2,'c':3,'d':4}
def exchange(dicts):
    for num in dicts.copy():
        middle = dicts[num]
        dicts[num] = num
        dicts[middle] = dicts.pop(num)
    new_dict = dicts
    return new_dict
print(exchange(dict1))

5. 编写一个函数，提取指定字符串中的所有的字母，然后拼接在一起后打印出来
   如:'12a&bc12d--' ---> 打印'abcd'

    list1 = []
    for x in str1:
        if x.isalpha():
            list1.append(x)
    new_str = str(list1)
    print(new_str)
    return new_str
print(get_letter('12abc12d'))

6. 写一个函数，求多个数的平均值

def average_n(*nums):
    print(nums)
    sum3 = 0
    for i in nums:
        sum3 += i
    average = sum3/len(nums)
    return average
print(average_n(60,66,88,78))

7. 写一个函数，默认求10的阶层，也可以求其他数的阶层

def jie_cheng(n=10):
    sum1 = 1
    for x in range(1,n+1):
        sum1 *= x
    return sum1
print(jie_cheng(8))

8. 写一个函数，可以对多个数进行不同的运算
   如: operation('+', 1, 2, 3) ---> 求 1+2+3的结果 operation('-', 10, 9) ---> 求 10-9的结果 operation('', 2, 4, 8, 10) ---> 求 24810的结构

def operation(symbol,*num6):
    if symbol == '+':
        sum6 = 0
        for num in num6:
            sum6 += num
    elif symbol == '-':
        sum6 = 2 * num6[0]
        for num in num6:
            sum6 -= num
    elif symbol == '*':
        sum6 = 1
        for num in num6:
            sum6 *= num
    return sum6
print(operation('-',10,9))

9.写一个函数，求指定列表中，指定的元素的个数

def list_num(list1, element):
    num = list1.count( element)
    return num
print(list_num([1,3,8,9,9,9,12,49],9))

10.写一个函数，获取指定列表中指定元素对应的下标(如果有多个，一起返回)

def list_id(list3, *elements):
    list9 = []
    for element in elements:
        id1 = list3.index(element)
        list9.append(id1)
    return list9

print(list_id([1,8,9,5,],1))