Python实验课4

实验一

实验源码

 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)

实验截图

实验二

task2.1Python

实验源码

 1 def func1(a,b,c,d,e,f):
 2     return [a,b,c,d,e,f]
 3 
 4 def func2(a,b,c,*,d,e,f):
 5     return [a,b,c,d,e,f]
 6 
 7 def func3(a,b,c,/,d,e,f):
 8     return [a,b,c,d,e,f]
 9 
10 print(func1(1,9,2,0,5,3))
11 print(func1(a=1,b=9,c=2,d=0,e=5,f=3))
12 print(func1(1,9,2,d=0,e=5,f=3))
13 
14 print(func2(11,99,22,d=0,e=55,f=33))
15 print(func2(a=11,b=99,c=22,d=0,e=55,f=33))
16 
17 
18 print(func3(111,999,222,0,555,333))
19 print(func3(111,999,222,d=0,e=555,f=333))

实验截图

task2.2Python

实验源码

1 list1 = [1,9,8,4]
2 
3 print(sorted(list1))
4 print(sorted(list1,reverse=True))
5 print(sorted(list1,True))

实验截图

task2.3Python

实验源码

1 def func(a,b,c,/,*,d,e,f):
2     return([a,b,c,d,e,f])
3 
4 print(func(1,2,3,d=4,e=5,f=6))

实验截图

实验三

实验源码

1 def solve(a, b, c):
 2     '''
 3     求解一元二次方程, 返回方程的两个根
 4     :para: a,b,c: float 方程系数
 5     :return: tuple
 6     '''
 7     delta = b*b - 4*a*c
 8     delta_sqrt = abs(delta)**0.5
 9     p1 = -b/2/a
10     p2 = delta_sqrt/2/a
11 
12     if delta >= 0:
13         root1 = p1 + p2
14         root2 = p1 - p2
15     else:
16         root1 = complex(p1, p2)
17         root2 = complex(p1, -p2)
18 
19     return root1, root2
20 
21 print(solve.__doc__)
22 while True:
23     try:
24         t = input('输入一元二次方程系数a b c, 或者，输入#结束: ')
25         if t == '#':
26             print('结束计算，退出')
27             break
28         a, b, c = map(float, t.split())
29         if a == 0:
30             raise ValueError('a = 0, 不是一元二次方程')
31     except ValueError as e:
32         print(repr(e))
33         print()
34     except:
35         print('有其它错误发生\n')
36     else:
37         root1, root2 = solve(a, b, c)
38         print(f'root1 = {root1:.2f}, root2 = {root2:.2f}')
39         print()

实验截图

 实验四

实验源码

 1 def list_generator(a,b,c=1):
 2     if type(c)==type(1):
 3         b = b + 1
 4         lst = range(a,b,c)
 5     else:
 6         b = b +0.5
 7         lst = []
 8         x = a
 9         while (x<b):
10             lst.append(x)
11             x +=c
12     return list(lst)
13 
14 
15 list1 = list_generator(-5, 5)
16 print(list1)
17 
18 list2 = list_generator(-5, 5, 2)
19 print(list2)
20 
21 list3 = list_generator(1, 5, 0.5)
22 print(list3)

实验截图

实验五

实验源码

 1 def is_prime(n):
 2     if n == 2:
 3         return True
 4     elif n != 1:
 5         for i in range(2,n):
 6             if n == 2:
 7                 return True
 8             elif n % i == 0:
 9                 break
10             else:
11                 return True
12 
13 for i in range(2,20+1,2):
14     flag = True
15     for j in range(2, i):
16         if is_prime(j) == True and is_prime(i - j) == True and flag == True:
17             print(f'{i}={j}+{i-j}')
18             flag = False

实验六

实验源码

1 def encoder(text):
 2     ls=list(text)
 3     for i in range(len(ls)):
 4         if 'a'<=ls[i].lower()<='u':
 5             ls[i]=chr(ord(ls[i])+5)
 6         elif 'v'<=ls[i].lower()<='z':
 7             ls[i]=chr(ord(ls[i])-21)
 8         else:
 9             pass
10     return ''.join(ls)
11 
12 def decoder(text):
13     ls=list(text)
14     for i in range(len(ls)):
15         if 'f'<=ls[i].lower()<='z':
16             ls[i]=chr(ord(ls[i])-5)
17         elif 'a'<=ls[i].lower()<='e':
18             ls[i]=chr(ord(ls[i])+21)
19         else:
20             pass
21     return ''.join(ls)
22 
23 
24 text = input('输入英文文本: ')
25 
26 encoded_text = encoder(text)
27 print('编码后的文本: ', encoded_text)
28 
29 decoded_text = decoder(encoded_text)
30 print('对编码后的文本解码: ', decoded_text)

实验七

实验源码

 1 def collatz(n):
 2     x=[n]
 3     while x[-1]!=1:
 4         if n%2==0:
 5             n=n//2
 6             x.append(n)
 7         else:
 8             n=n*3+1
 9             x.append(n)
10     return x
11 
12 try:
13     n=int(input('Enter a positive integer:'))
14     if n<=0:
15         raise
16 except:
17     print('Error: must be a positive integer')
18 else:
19     print(collatz(n))

实验截图

实验八

实验源码

 1 def func(n):
 2     if n == 1:
 3         ans = 2  - 1
 4     else:
 5         ans = 2 * func(n-1) +1
 6         n -= 1
 7     return ans
 8 while True:
 9     x = input()
10     if x == '#':
11         print('计算结束')
12         break
13     n = int(x)
14     ans = func(n)
15     print(f'n = {n}, ans = {ans}')

实验截图