实验四

task
 1 print(sum)
 2 sum = 42
 3 print(sum)
 4 
 5 def inc(n):
 6     sum=n+1
 7     print(sum)
 8     return sum
 9 
10 sum=inc(7)+inc(7)
11 print(sum)

不是内置,全局,局部,全局

task2

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

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))

task3

def solve(a,b,c):
    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()

task4

def list_generator(x,y,z=1):
    a=[]
    while x<=y:
        a.append(x)
        x=x+z
    return a
list1=list_generator(-5,5)
print(list1)
list2=list_generator(-5,5,2)
print(list2)
list3=list_generator(1,5,0.5)
print(list3)

task5

def is_prime(x):
    for i in range(2,x):
        if x%i==0:
            return False
    return True
for i in range(4,21,2):
    for t in range(2,i):
        if is_prime(t)==True and is_prime(i-t)==True:
            print(f'{i}={t}+{i-t}')
            break

task6

def encoder(x):
    y=list(x)
    for j in range(len(y)):
        x=y[j]
        a=[chr(i) for i in range(97,123)]
        b=[chr(i) for i in range(65,91)]
        if x in a:
            t=a.index(x)+5
            if t>25:
                t=t-26
            y[j]=a[t]
        elif x in b:
            s = b.index(x) + 5
            if s>25:
                s=s-26
            y[j]=b[s]
        else:
            y[j]=x
    return ''.join(y)
def decoder(x):
    y=list(x)
    for j in range(len(y)):
        x=y[j]
        a=[chr(i) for i in range(97,123)]
        b=[chr(i) for i in range(65,91)]
        if x in a:
            t=a.index(x)-5
            if t<0:
                t=t+26
            y[j]=a[t]
        elif x in b:
            s = b.index(x)-5
            if s<0:
                s=s+26
            y[j]=b[s]
        else:
            y[j]=x
    return ''.join(y)
t=input('输入英文文本:')
a=encoder(t)
b=decoder(a)
print(f'编码后的文本:{a}')
print(f'对编码后的文本解码:{b}')

task7

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

 

posted @ 2022-05-10 20:31  雷建彬  阅读(2)  评论(1编辑  收藏  举报