刷题继续
上一期和大家分享了前10道题，今天继续来刷11~20
Question 11:
Write a program which accepts a sequence of comma separated 4 digit binary numbers as its input and then check whether they are divisible by 5 or not. The numbers that are divisible by 5 are to be printed in a comma separated sequence.Example:
0100,0011,1010,1001Then the output should be:
1010Notes: Assume the data is input by console.
解法一
def check(x): # check function returns true if divisible by 5
return int(x,2)%5 == 0 # int(x,b) takes x as string and b as base from which
# it will be converted to decimal
data = input().split(',')
data = list(filter(check,data)) # in filter(func,object) function, elements are picked from 'data' if found True by 'check' function
print(",".join(data))解法二
value = []
items=[int(x) for x in input().split(',')]
result = " ".join(str(x) for x in items if x %5==0 )
print(",".join(result))解法三
data = input().split(',')
data = list(filter(lambda i:int(i,2)%5==0,data))
print(",".join(data))Question 12:
Write a program, which will find all such numbers between 1000 and 3000 (both included) such that each digit of the number is an even number.The numbers obtained should be printed in a comma-separated sequence on a single line.
解法一
values = []
for i in range(1000, 3001):
s = str(i)
if (int(s[0])%2==0) and (int(s[1])%2==0) and (int(s[2])%2==0) and (int(s[3])%2==0):
values.append(s)
print (",".join(values))
解法二
lst = []
for i in range(1000,3001):
flag = 1
for j in str(i): # every integer number i is converted into string
if ord(j)%2 != 0: # ord returns ASCII value and j is every digit of i
flag = 0 # flag becomes zero if any odd digit found
if flag == 1:
lst.append(str(i)) # i is stored in list as string
print(",".join(lst))
解法三
def check(element):
return all(ord(i)%2 == 0 for i in element) # all returns True if all digits i is even in element
lst = [str(i) for i in range(1000,3001)] # creates list of all given numbers with string data type
lst = list(filter(check,lst)) # filter removes element from list if check condition fails
print(",".join(lst))
解法四
lst = [str(i) for i in range(1000,3001)]
lst = list(filter(lambda i:all(ord(j)%2 == 0 for j in i),lst )) # using lambda to define function inside filter function
print(",".join(lst))
Question 13:
Write a program that accepts a sentence and calculate the number of letters and digits.Suppose the following input is supplied to the program:
hello world! 123Then, the output should be:
LETTERS 10
DIGITS 3解法一
text_input = input()
d={"DIGITS":0, "LETTERS":0,'SPACE':0}
d['DIGITS']= sum(c.isdigit() for c in text_input)
d['LETTERS']= sum(c.isalpha() for c in text_input)
d['SPACE'] = sum(c.isspace() for c in text_input)
for k,v in d.items():
print(k,v)
解法二
word = input()
letter,digit = 0,0
for i in word:
if ('a'<=i and i<='z') or ('A'<=i and i<='Z'):
letter+=1
if '0'<=i and i<='9':
digit+=1
print("LETTERS {0}\nDIGITS {1}".format(letter,digit))
解法三
word = input()
letter,digit = 0,0
for i in word:
letter+=i.isalpha() # returns True if alphabet
digit+=i.isnumeric() # returns True if numeric
print("LETTERS %d\nDIGITS %d"%(letter,digit)) # two different types of formating method is shown in both solution
Question 14:
Write a program that accepts a sentence and calculate the number of upper case letters and lower case letters.Suppose the following input is supplied to the program:
Hello world!Then, the output should be:
UPPER CASE 1
LOWER CASE 9解法一
word = input()
upper,lower = 0,0
for i in word:
if 'a'<=i and i<='z' :
lower+=1
if 'A'<=i and i<='Z':
upper+=1
print("UPPER CASE {0}\nLOWER CASE {1}".format(upper,lower))解法二
text_input = input()
d={"UPPER CASE":0, "LOWER CASE":0}
for c in text_input:
if c.isupper():
d["UPPER CASE"]+=1
elif c.islower():
d["LOWER CASE"]+=1
else:
pass
print ("UPPER CASE", d["UPPER CASE"])
print ("LOWER CASE", d["LOWER CASE"])
解法三
word = input()
upper = sum(1 for i in word if i.isupper())
lower = sum(1 for i in word if i.islower())
print("UPPER CASE {0}\nLOWER CASE {1}".format(upper,lower))Question 15:
Write a program that computes the value of a+aa+aaa+aaaa with a given digit as the value of a.Suppose the following input is supplied to the program:
9Then, the output should be:
11106解法一
a = input()
total,tmp = 0,str() # initialing an integer and empty string
for i in range(4):
tmp+=a # concatenating 'a' to 'tmp'
total+=int(tmp) # converting string type to integer type
print(total)
解法二
a = input()
total = int(a) + int(2*a) + int(3*a) + int(4*a) # N*a=Na, for example a="23", 2*a="2323",3*a="232323"
print(total)
Question 16:
Use a list comprehension to square each odd number in a list. The list is input by a sequence of comma-separated numbers.
Suppose the following input is supplied to the program:
1,2,3,4,5,6,7,8,9Then, the output should be:
1,3,5,7,9解法一
values = input()
numbers = [x for x in values.split(",") if int(x)%2!=0]
print (",".join(numbers))
Question 17:
Write a program that computes the net amount of a bank account based a transaction log from console input. The transaction log format is shown as following:
D 100
W 200- D means deposit while W means withdrawal.
Suppose the following input is supplied to the program:
D 300
D 300
W 200
D 100Then, the output should be:
500解法一
netAmount = 0
while True:
s = input()
if not s:
break
values = s.split(" ")
operation = values[0]
amount = int(values[1])
if operation=="D":
netAmount+=amount
elif operation=="W":
netAmount-=amount
else:
pass
print(netAmount)
解法二
total = 0
while True:
s = input().split()
if not s: # break if the string is empty
break
cm,num = map(str,s)
if cm=='D':
total+=int(num)
if cm=='W':
total-=int(num)
print(total)Question 18:
A website requires the users to input username and password to register. Write a program to check the validity of password input by users.Following are the criteria for checking the password:
- At least 1 letter between [a-z]
- At least 1 number between [0-9]
- At least 1 letter between [A-Z]
- At least 1 character from [$#@]
- Minimum length of transaction password: 6
- Maximum length of transaction password: 12
Your program should accept a sequence of comma separated passwords and will check them according to the above criteria. Passwords that match the criteria are to be printed, each separated by a comma.Example
If the following passwords are given as input to the program:
ABd1234@1,a F1#,2w3E*,2We3345Then, the output of the program should be:
ABd1234@1解法一
import re
value = []
items=[x for x in input().split(',')]
for p in items:
if (len(p)<6 or len(p)>12):
break
elif not re.search("[a-z]",p):
break
elif not re.search("[0-9]",p):
break
elif not re.search("[A-Z]",p):
break
elif not re.search("[$#@]",p):
break
elif re.search("\s",p):
break
else:
value.append(p)
break
print (",".join(value))解法二
def is_low(x): # Returns True if the string has a lowercase
for i in x:
if 'a'<=i and i<='z':
return True
return False
def is_up(x): # Returns True if the string has a uppercase
for i in x:
if 'A'<= i and i<='Z':
return True
return False
def is_num(x): # Returns True if the string has a numeric digit
for i in x:
if '0'<=i and i<='9':
return True
return False
def is_other(x): # Returns True if the string has any "$#@"
for i in x:
if i=='$' or i=='#' or i=='@':
return True
return False
s = input().split(',')
lst = []
for i in s:
length = len(i)
if 6 <= length and length <= 12 and is_low(i) and is_up(i) and is_num(i) and is_other(i): #Checks if all the requirments are fulfilled
lst.append(i)
print(",".join(lst))
解法三
def check(x):
cnt = (6<=len(x) and len(x)<=12)
for i in x:
if i.isupper():
cnt+=1
break
for i in x:
if i.islower():
cnt+=1
break
for i in x:
if i.isnumeric():
cnt+=1
break
for i in x:
if i=='@' or i=='#'or i=='$':
cnt+=1
break
return cnt == 5 # counting if total 5 all conditions are fulfilled then returns True
s = input().split(',')
lst = filter(check,s) # Filter function pick the words from s, those returns True by check() function
print(",".join(lst))
解法四
import re
s = input().split(',')
lst = []
for i in s:
cnt = 0
cnt+=(6<=len(i) and len(i)<=12)
cnt+=bool(re.search("[a-z]",i)) # here re module includes a function re.search() which returns the object information
cnt+=bool(re.search("[A-Z]",i)) # of where the pattern string i is matched with any of the [a-z]/[A-z]/[0=9]/[@#$] characters
cnt+=bool(re.search("[0-9]",i)) # if not a single match found then returns NONE which converts to False in boolean
cnt+=bool(re.search("[@#$]",i)) # expression otherwise True if found any.
if cnt == 5:
lst.append(i)
print(",".join(lst))
Question 19:
You are required to write a program to sort the (name, age, score) tuples by ascending order where name is string, age and score are numbers. The tuples are input by console. The sort criteria is:
- 1: Sort based on name
- 2: Then sort based on age
- 3: Then sort by score
The priority is that name > age > score.If the following tuples are given as input to the program:
Tom,19,80
John,20,90
Jony,17,91
Jony,17,93
Json,21,85Then, the output of the program should be:
[('John', '20', '90'), ('Jony', '17', '91'), ('Jony', '17', '93'), ('Json', '21', '85'), ('Tom', '19', '80')]解法一
lst = []
while True:
s = input().split(',')
if not s[0]: # breaks for blank input
break
lst.append(tuple(s))
lst.sort(key= lambda x:(x[0],x[1],x[2]))
print(lst)
Question 20:
Define a class with a generator which can iterate the numbers, which are divisible by 7, between a given range 0 and n.
解法一
class Test:
def generator(self,n):
return [i for i in range(n) if i%7==0]
n = int(input())
num = Test()
lst = num.generator(n)
print(lst)
源代码下载
这十道题的代码在我的github上，如果大家想看一下每道题的输出结果，可以点击以下链接下载：
我的运行环境Python 3.6+,如果你用的是Python 2.7版本，绝大多数不同就体现在以下3点：
- raw_input()在Python3中是input()
- print需要加括号
- fstring可以换成.format(),或者%s，%d
谢谢大家，我们下期见！希望各位朋友不要吝啬，把每道题的更高效的解法写在评论里，我们一起进步！！！
