实验四

实验一:
print
(sum) sum = 42 print(sum) def inc(n): sum = n+1 print(sum) return sum sum = inc(7) + inc(7) print(sum)

问题:1.内置函数2.全局变量3.局部变量4.全局变量

实验二:

def func1(a, b, c, d, e, f):
    '''返回参数a,b,c,d,e,f构成的列表
    默认,参数按位置传递; 也支持关键字传递
    '''
    return [a,b,c,d,e,f]
def func2(a, b, c,*, d, e, f):
    '''
    返回参数a,b,c,d,e,f构成的列表
    *后面的参数只能按关键字传递
    '''
    return [a,b,c,d,e,f]
def func3(a, b, c, /, d, e, f):
    '''
    返回参数a,b,c,d,e,f构成的列表
    /前面的参数只能按位置传递
    '''
    return [a,b,c,d,e,f]
print( func1(1,9,2,0,5,3) )
print( func1(a=1, b=9, c=2, d=0, e=5, f=3) )
print( func1(1,9,2, f=3, d=0, e=5))

print( func2(11, 99, 22, d=0, e=55, f=33) )
print( func2(a=11, b=99, c=22, d=0, e=55, f=33) )

print( func3(111, 999, 222, 0, 555, 333))
print( func3(111, 999, 222, d=0, e=555, f=333) )

list1 = [1, 9, 8, 4]
print( sorted(list1) )
print( sorted(list1, reverse=True) )
print( sorted(list1, True) )

问题2.2:是的

def func(a, b, c, /, *, d, e, f):
    return( [a,b,c,d,e,f] )

print(func(1, 2, 3, d=4, e=5, f=6))

实验三:

def solve(a, b, c):
    '''
    求解一元二次方程, 返回方程的两个根
    :para: a,b,c: int 方程系数
    :return: tuple
    '''
    delta = b*b - 4*a*c
    delta_sqrt = abs(delta)**0.5
    p1 = -b/2/a;
    p2 = delta_sqrt/2/a


    if delta>=0:
        root1 = p1 + p2
        root2 = p1 - p2
    else:
        root1 = complex(p1, p2)
        root2 = complex(p1, -p2)

    return root1, root2

print(solve.__doc__)
while True:
    try:
        a,b,c = eval(input('Enter eqution coefficient: '))
        if a == 0:
            raise
    except:
        print('invalid input, or, a is zero')
        break
    else:
        root1, root2 = solve(a, b, c)
        print(f'root1 = {root1:.2f}, root2 = {root2:.2f}')
        print()

实验四:

def list_generator (begin,end,step=1):
    list=[]
    while begin<=end:
        list.append(begin)
        begin=begin+step
    return list

list1=list_generator(-5, 5)
print(list1)

list2=list_generator(-5, 5, 2)
print(list2)

list3=list_generator(1, 5, 0.5)
print(list3)

实验五:

def is_prime(n):
    if n < 2:
        return False
    for i in range(2,int(n**0.5)+1):
        if n % i == 0:
            return False
    return True

h=[i for i in range(21)]
for x in h[::2]:
    for a in range(0,21):
        if is_prime(a) is True:
            if is_prime(x-a) is True:
                print(f'{x}={a}+{x-a}')
                break
            else:
                a+=1
        else:
            a+=1

实验六:

def encoder(strs):
    a=list(strs)
    i=0
    while i <len(strs):
        b = ord(a[i])
        if 65<=b<=85 or 97<=b<=117:
            c=chr(b+5)

        elif 85<=b<=90 or 117<=b<=122:
            c=chr(b-21)
        else:
            c=chr(b)
        a[i]=c
        i+=1
    return ''.join(a)



def decoder(strs):
    a = list(strs)
    i=0
    while i < len(strs):
        b = ord(a[i])
        if 70<=b<=90 or 102<=b<=122:
            c=chr(b-5)
        elif 65<=b<=70 or 97<=b<=102:
            c=chr(b+21)
        else:
            c=chr(b)
        a[i] = c
        i+=1
    return ''.join(a)

a=input('输入英文文本: ')
print(f'编码后的文本:{encoder(a)}')
print(f'对编码后的文本解码:{decoder(encoder(a))}')

实验七:

def collatz(n):
    x=[n]
    while n!=1:
        if n%2==0:
            n=n/2
        else:
            n=3*n+1
        x.append(int(n))
    return x
try:
    n=int(input('Enter a positive integer:'))
    if n<=0:
        raise
except:
    print('Error: must be a positive integer')
else:
    print(collatz(n))

 

posted @ 2022-05-08 19:31  杜雨萱  阅读(14)  评论(2编辑  收藏  举报