Python3.x basic learning-function usage (4)

1. Given two lists, A = [1,2,3,4,5,6,7,1,2,3] and B = [4,5,6,7,8,9,10,9 , 8,11], 
please use python to find the same elements in A and B and put them in list D. Find the different elements in A and B and put them in list C. Make
sure that the elements in the two lists of C and D are not repeat.
A = [1,2,3,4,5,6,7,1,2,3]
B=[4,5,6,7,8,9,10,9,8,11]
print(set(A))
# {1, 2, 3, 4, 5, 6, 7}

print(set(B))
# {4, 5, 6, 7, 8, 9, 10, 11}

D = set(A) & set(B)
C = set(A) ^ set(B)
print(D)
# {4, 5, 6, 7}

print(C)
# {1, 2, 3, 8, 9, 10, 11}
2. Packaging function, can judge whether a number is even
def func (n):
     if n% 2 == 0:
         print ( " % d is even " % n)
     else :
         print ( " % d is odd " % n)

func ( 11 )
 # 11 is odd

 

3. Encapsulation function, can realize the printing of all even numbers between 1-n
def func(n):
    for i in range(1,n+1):
        if i%2==0:
            print(i)

func(10)
# 2
# 4
# 6
# 8
# 10
4. Encapsulation function, you can find the maximum value in the integer list
lst = [2,7,3,9,1,4]
def func(n):
    x = n[0]
    for i in n:
        if i>x:
            x=i
    return x
print(func(lst))
# 9
5. Check the length of the incoming list, if it is greater than 2, keep the content of the first two lengths, and return the new content to the caller
lst = [2,7,3,9,1,4]
def func(n):
    if len(lst)>2:
        return lst[:2]
print(func(lst))
# [2, 7]
6. Encapsulation function, can complete the reverse order of the list, without using the built-in function
lst = [2,7,3,9,1,4]
# print(sorted(lst,reverse=True))
# print(lst.sort())
# print(lst)

def func(n):
    for i in range(len(n)-1):
        for j in range(len(n)-i-1):
            if n[j]<n[j+1]:
                n [j], n [j +1] = n [j + 1 ], n [j]
     return n
 print (func (lst))
 # [9, 7, 4, 3, 2, 1] 

# or
lst1 = [2,7,3,9,1,4]
print(lst1[::-1])
# [4, 1, 9, 3, 7, 2]


7. Encapsulation function, you can judge whether an integer is a prime number 
# For a positive integer n, if all integers between 2 and x are divided and cannot be divided, then n is a prime number
from math import sqrt
 def func (n):
     if n == 1 :
         return  ' is prime number ' 
    else :
         for i in range (2, int (sqrt (n)) + 1 ):
             if n% i == 0:
                 return  ' Not a prime number ' 
    return  ' is a prime number ' 
print (func (2 ))
 #is a prime number
8. Encapsulation function, you can print all the prime numbers between 1-a, and wrap every 4
def func(n):
    count=0
    for i in range(1,n+1):
        for j in range(2,int(sqrt(i)+1)):
            if i%j==0:
                break
        else:
            count=count+1
            print(i,end=' ')
            if count%4==0:
                print("\n")


print(func(100))
# 1 2 3 5
#
# 7 11 13 17
#
# 19 23 29 31
#
# 37 41 43 47
#
# 53 59 61 67
#
# 71 73 79 83
#
# 89 97 None

9. Encapsulation function, can print all prime numbers between 2-a, use recursive function

def func(n):
    if n==2:
        return 2
    for i in range(2,int(sqrt(n)+1)):
        if n%i==0:
           return func(n-1)
    else:
        print(n)
        return func(n-1)

print(func(100))

# 97
# 89
# 83
# 79
# 73
# 71
# 67
# 61
# 59
# 53
# 47
# 43
# 41
# 37
# 31
# 29
# 23
# 19
# 17
# 13
# 11
# 7
# 5
# 3
# 2
10. Encapsulate functions, find out the elements of the odd index of the incoming list and insert into the new list
def func(n):
    newlist=[]
    for i in range(0,len(n)+1,2):
        newlist.append(n[i])
    return newlist

list =['a','b','c','d','e','f','g','h','i','j','k']
print(func(list))
# ['a', 'c', 'e', 'g', 'i', 'k']
11. Encapsulation function, judge whether a number is the number of daffodils (the number of daffodils is a three-digit number, and the sum of the cube of each number is also equal to this number.)

s = input ( " Please enter a number: " )
 if len (s) == 3 :
   result = int (s [0]) ** 3 + int (s [1]) ** 3 + int (s [2]) ** 3
    if int (s) == result:
        print ( " is a daffodil number " )
    else :
        print ( " Not a daffodil number " )
 else :
    print ( " Please enter three digits " )

 



















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Origin www.cnblogs.com/johnsonbug/p/12702639.html