So I'm a little confused as far as putting this small code together. My teacher gave me this info:
Iterate over the string and remove any triplicated letters (e.g.
"byeee mmmy friiiennd" becomes "bye my friennd"). You may assume any
immediate following same letters are a triplicate.
I've mostly only seen examples for duplicates, so how do I remove triplicates? My code doesn't return anything when I run it.
def removeTriplicateLetters(i):
result = ''
for i in result:
if i not in result:
result.append(i)
return result
def main():
print(removeTriplicateLetters('byeee mmmy friiiennd'))
main()
I have generalized the scenario with "n". In your case, you can pass n=3 as below
def remove_n_plicates(input_string, n):
i=0
final_string = ''
if not input_string:
return final_string
while(True):
final_string += input_string[i]
if input_string[i:i+n] == input_string[i]*n:
i += n
else:
i += 1
if i >= len(input_string):
break
return final_string
input_string = "byeee mmmy friiiennd"
output_string = remove_n_plicates(input_string, 3)
print(output_string)
# bye my friennd
You can use this for any "n" value now (where n > 0 and n < length of input string)
Your code returns an empty string because that's exactly what you coded:
result = ''
for i in result:
...
return result
Since result is an empty string, you don't enter the loop at all.
If you did enter the loop you couldn't return anything:
for i in result:
if i not in result:
The if makes no sense: to get to that statement, i must be in result
Instead, do as #newbie showed you. Iterate through the string, looking at a 3-character slice. If the slice is equal to 3 copies of the first character, then you've identified a triplet.
if input_string[i:i+n] == input_string[i]*n:
Without going in to writing the code to resolve the problem.
When you iterate over the string, add that iteration to a new string.
If the next iteration is the same as the previous iteration then do not add that to the new string.
This will catch both the triple and the double characters in your problem.
Tweaked a previous answer to remove a few lines that were not needed.
def remove_n_plicates(input_string, n):
i=0
result = ''
while(True):
result += input_string[i]
if input_string[i:i+n] == input_string[i]*n:
i += n
else:
i += 1
if i >= len(input_string):
break
return result
input_string = "byeee mmmy friiiennd"
output_string = remove_n_plicates(input_string, 3)
print(output_string)
# bye my friennd
Here's a fun way using itertools.groupby:
def removeTriplicateLetters(s):
return ''.join(k*(l//3+l%3) for k,l in ((k,len(list(g))) for k, g in groupby(s)))
>>> removeTriplicateLetters('byeee mmmy friiiennd')
'bye my friennd'
just modifying #newbie solution and using stack data structure as solution
def remove_n_plicates(input_string, n):
if input_string =='' or n<1:
return None
w = ''
c = 0
if input_string!='':
tmp =[]
for i in range(len(input_string)):
if c==n:
w+=str(tmp[-1])
tmp=[]
c =0
if tmp==[]:
tmp.append(input_string[i])
c = 1
else:
if input_string[i]==tmp[-1]:
tmp.append(input_string[i])
c+=1
elif input_string[i]!=tmp[-1]:
w+=str(''.join(tmp))
tmp=[input_string[i]]
c = 1
w+=''.join(tmp)
return w
input_string = "byeee mmmy friiiennd nnnn"
output_string = remove_n_plicates(input_string, 3)
print(output_string)
output
bye my friennd nn
so this is a bit dirty but it's short and works
def removeTriplicateLetters(i):
result,string = i[:2],i[2:]
for k in string:
if result[-1]==k and result[-2]==k:
result=result[:-1]
else:
result+=k
return result
print(removeTriplicateLetters('byeee mmmy friiiennd'))
bye my friennd
You have already got a working solution. But here, I come with another way to achieve your goal.
def removeTriplicateLetters(sentence):
"""
:param sentence: The sentence to transform.
:param words: The words in the sentence.
:param new_words: The list of the final words of the new sentence.
"""
words = sentence.split(" ") # split the sentence into words
new_words = []
for word in words: # loop through words of the sentence
new_word = []
for char in word: # loop through characters in a word
position = word.index(char)
if word.count(char) >= 3:
new_word = [i for i in word if i != char]
new_word.insert(position, char)
new_words.append(''.join(new_word))
return ' '.join(new_words)
def main():
print(removeTriplicateLetters('byeee mmmy friiiennd'))
main()
Output: bye my friennd
Related
I'm working on an assignment and have gotten stuck on a particular task. I need to write two functions that do similar things. The first needs to correct capitalization at the beginning of a sentence, and count when this is done. I've tried the below code:
def fix_capitalization(usrStr):
count = 0
fixStr = usrStr.split('.')
for sentence in fixStr:
if sentence[0].islower():
sentence[0].upper()
count += 1
print('Number of letters capitalized: %d' % count)
print('Edited text: %s' % fixStr)
Bu receive an out of range error. I'm getting an "Index out of range error" and am not sure why. Should't sentence[0] simply reference the first character in that particular string in the list?
I also need to replace certain characters with others, as shown below:
def replace_punctuation(usrStr):
s = list(usrStr)
exclamationCount = 0
semicolonCount = 0
for sentence in s:
for i in sentence:
if i == '!':
sentence[i] = '.'
exclamationCount += 1
if i == ';':
sentence[i] = ','
semicolonCount += 1
newStr = ''.join(s)
print(newStr)
print(semicolonCount)
print(exclamationCount)
But I'm struggling to figure out how to actually do the replacing once the character is found. Where am I going wrong here?
Thank you in advance for any help!
I would use str.capitalize over str.upper on one character. It also works correctly on empty strings. The other major improvement would be to use enumerate to also track the index as you iterate over the list:
def fix_capitalization(s):
sentences = [sentence.strip() for sentence in s.split('.')]
count = 0
for index, sentence in enumerate(sentences):
capitalized = sentence.capitalize()
if capitalized != sentence:
count += 1
sentences[index] = capitalized
result = '. '.join(sentences)
return result, count
You can take a similar approach to replacing punctuation:
replacements = {'!': '.', ';': ','}
def replace_punctuation(s):
l = list(s)
counts = dict.fromkeys(replacements, 0)
for index, item in enumerate(l):
if item in replacements:
l[index] = replacements[item]
counts[item] += 1
print("Replacement counts:")
for k, v in counts.items():
print("{} {:>5}".format(k, v))
return ''.join(l)
There are better ways to do these things but I'll try to change your code minimally so you will learn something.
The first function's issue is that when you split the sentence like "Hello." there will be two sentences in your fixStr list that the last one is an empty string; so the first index of an empty string is out of range. fix it by doing this.
def fix_capitalization(usrStr):
count = 0
fixStr = usrStr.split('.')
for sentence in fixStr:
# changed line
if sentence != "":
sentence[0].upper()
count += 1
print('Number of letters capitalized: %d' % count)
print('Edited text: %s' % fixStr)
In second snippet you are trying to write, when you pass a string to list() you get a list of characters of that string. So all you need to do is to iterate over the elements of the list and replace them and after that get string from the list.
def replace_punctuation(usrStr):
newStr = ""
s = list(usrStr)
exclamationCount = 0
semicolonCount = 0
for c in s:
if c == '!':
c = '.'
exclamationCount += 1
if c == ';':
c = ','
semicolonCount += 1
newStr = newStr + c
print(newStr)
print(semicolonCount)
print(exclamationCount)
Hope I helped!
Python has a nice build in function for this
for str in list:
new_str = str.replace('!', '.').replace(';', ',')
You can write a oneliner to get a new list
new_list = [str.replace('!', '.').replace(';', ',') for str in list]
You also could go for the split/join method
new_str = '.'.join(str.split('!'))
new_str = ','.join(str.split(';'))
To count capitalized letters you could do
result = len([cap for cap in str if str(cap).isupper()])
And to capitalize them words just use the
str.capitalize()
Hope this works out for you
I was given a task to input multiple lines each consisting of multiple words.The task is to uppercase the words with an odd length and lowercase the words with an
even length.
My code now looks like this, can you help me to solve it right?
first = []
while True:
line = input().split()
first.append(line)
if len(line) < 1:
break
for i in first:
for j in i:
if len(line[i][j]) % 2 == 0:
line[i][j] = line[i][j].lower()
elif len(line[i][j]) % 2 != 0:
line[i][j] = line[i][j].upper()
print(first[i])
it should look like this
i and j are not an indexes, they are the sublists and words themselves.You can do:
for i in first: # i is a list of strings
for j in range(len(i)): # you do need the index to mutate the list
if len(i[j]) % 2 == 0:
i[j] = i[j].lower()
else:
i[j] = i[j].upper()
print(' '.join(i))
So looking at the input output in your image, here is a better solution
sentences = []
while True:
word_list = input().split()
sentences = [*sentences, word_list]
if len(word_list) < 1:
break
So now that you have your input from command line you can do
[word.upper() if len(word)%2 == 1 else word.lower() for word_list in sentences for word in word_list]
or you could extract into a function
def apply_case(word):
if len(word)%2:
return word.upper()
return word.lower()
new_sentences = [apply_case(word) for word_list in sentences for word in word_list]
now you can print it like
output = "\n".join([" ".join(word_list) for word_list in new_sentences])
print(output)
You forgot to join the lines back together. Furthermore from a software design point of view, you are doing to much in the code fragment: it is better to encapsulate the functionalities in functions, like:
def wordcase(word):
if len(word) % 2 == 0: # even
return word.lower()
else: # odd
return word.upper()
Then we can even perform the processing "online" (as in line-per-line):
while True:
line = input()
if not line:
break
else:
print(' '.join(wordcase(word) for word in line.split()))
I don't think you need do be using i or j. You can just loop over the words in your string.
Further, although it probably won't speed things up, you don't need the elif, you can just use an else. There are only two options, odd and even so you only need to check it once.
sentance = 'I am using this as a test string with many words'
wordlist = sentance.split()
fixed_wordlist = []
for word in wordlist:
if len(word)%2==0:
fixed_wordlist.append(word.lower())
else:
fixed_wordlist.append(word.upper())
print(sentance, '\n', wordlist, '\n', fixed_wordlist)
i got homework to do "Run Length Encoding" in python and i wrote a code but it is print somthing else that i dont want. it prints just the string(just like he was written) but i want that it prints the string and if threre are any characthers more than one time in this string it will print the character just one time and near it the number of time that she appeard in the string. how can i do this?
For example:
the string : 'lelamfaf"
the result : 'l2ea2mf2
def encode(input_string):
count = 1
prev = ''
lst = []
for character in input_string:
if character != prev:
if prev:
entry = (prev, count)
lst.append(entry)
#print lst
count = 1
prev = character
else:
count += 1
else:
entry = (character, count)
lst.append(entry)
return lst
def decode(lst):
q = ""
for character, count in lst:
q += character * count
return q
def main():
s = 'emanuelshmuel'
print decode(encode(s))
if __name__ == "__main__":
main()
Three remarks:
You should use the existing method str.count for the encode function.
The decode function will print count times a character, not the character and its counter.
Actually the decode(encode(string)) combination is a coding function since you do not retrieve the starting string from the encoding result.
Here is a working code:
def encode(input_string):
characters = []
result = ''
for character in input_string:
# End loop if all characters were counted
if set(characters) == set(input_string):
break
if character not in characters:
characters.append(character)
count = input_string.count(character)
result += character
if count > 1:
result += str(count)
return result
def main():
s = 'emanuelshmuel'
print encode(s)
assert(encode(s) == 'e3m2anu2l2sh')
s = 'lelamfaf'
print encode(s)
assert(encode(s) == 'l2ea2mf2')
if __name__ == "__main__":
main()
Came up with this quickly, maybe there's room for optimization (for example, if the strings are too large and there's enough memory, it would be better to use a set of the letters of the original string for look ups rather than the list of characters itself). But, does the job fairly efficiently:
text = 'lelamfaf'
counts = {s:text.count(s) for s in text}
char_lst = []
for l in text:
if l not in char_lst:
char_lst.append(l)
if counts[l] > 1:
char_lst.append(str(counts[l]))
encoded_str = ''.join(char_lst)
print encoded_str
This question already has answers here:
How can I invert (swap) the case of each letter in a string?
(8 answers)
How can I use `return` to get back multiple values from a loop? Can I put them in a list?
(2 answers)
Closed 6 months ago.
I would like to change the chars of a string from lowercase to uppercase.
My code is below, the output I get with my code is a; could you please tell me where I am wrong and explain why?
Thanks in advance
test = "AltERNating"
def to_alternating_case(string):
words = list(string)
for word in words:
if word.isupper() == True:
return word.lower()
else:
return word.upper()
print to_alternating_case(test)
If you want to invert the case of that string, try this:
>>> 'AltERNating'.swapcase()
'aLTernATING'
There are two answers to this: an easy one and a hard one.
The easy one
Python has a built in function to do that, i dont exactly remember what it is, but something along the lines of
string.swapcase()
The hard one
You define your own function. The way you made your function is wrong, because
iterating over a string will return it letter by letter, and you just return the first letter instead of continuing the iteration.
def to_alternating_case(string):
temp = ""
for character in string:
if character.isupper() == True:
temp += character.lower()
else:
temp += word.upper()
return temp
Your loop iterates over the characters in the input string. It then returns from the very first iteration. Thus, you always get a 1-char return value.
test = "AltERNating"
def to_alternating_case(string):
words = list(string)
rval = ''
for c in words:
if word.isupper():
rval += c.lower()
else:
rval += c.upper()
return rval
print to_alternating_case(test)
That's because your function returns the first character only. I mean return keyword breaks your for loop.
Also, note that is unnecessary to convert the string into a list by running words = list(string) because you can iterate over a string just as you did with the list.
If you're looking for an algorithmic solution instead of the swapcase() then modify your method this way instead:
test = "AltERNating"
def to_alternating_case(string):
res = ""
for word in string:
if word.isupper() == True:
res = res + word.lower()
else:
res = res + word.upper()
return res
print to_alternating_case(test)
You are returning the first alphabet after looping over the word alternating which is not what you are expecting. There are some suggestions to directly loop over the string rather than converting it to a list, and expression if <variable-name> == True can be directly simplified to if <variable-name>. Answer with modifications as follows:
test = "AltERNating"
def to_alternating_case(string):
result = ''
for word in string:
if word.isupper():
result += word.lower()
else:
result += word.upper()
return result
print to_alternating_case(test)
OR using list comprehension :
def to_alternating_case(string):
result =[word.lower() if word.isupper() else word.upper() for word in string]
return ''.join(result)
OR using map, lambda:
def to_alternating_case(string):
result = map(lambda word:word.lower() if word.isupper() else word.upper(), string)
return ''.join(result)
You should do that like this:
test = "AltERNating"
def to_alternating_case(string):
words = list(string)
newstring = ""
if word.isupper():
newstring += word.lower()
else:
newstring += word.upper()
return alternative
print to_alternating_case(test)
def myfunc(string):
i=0
newstring=''
for x in string:
if i%2==0:
newstring=newstring+x.lower()
else:
newstring=newstring+x.upper()
i+=1
return newstring
contents='abcdefgasdfadfasdf'
temp=''
ss=list(contents)
for item in range(len(ss)):
if item%2==0:
temp+=ss[item].lower()
else:
temp+=ss[item].upper()
print(temp)
you can add this code inside a function also and in place of print use the return key
string=input("enter string:")
temp=''
ss=list(string)
for item in range(len(ss)):
if item%2==0:
temp+=ss[item].lower()
else:
temp+=ss[item].upper()
print(temp)
Here is a short form of the hard way:
alt_case = lambda s : ''.join([c.upper() if c.islower() else c.lower() for c in s])
print(alt_case('AltERNating'))
As I was looking for a solution making a all upper or all lower string alternating case, here is a solution to this problem:
alt_case = lambda s : ''.join([c.upper() if i%2 == 0 else c.lower() for i, c in enumerate(s)])
print(alt_case('alternating'))
You could use swapcase() method
string_name.swapcase()
or you could be a little bit fancy and use list comprehension
string = "thE big BROWN FoX JuMPeD oVEr thE LAZY Dog"
y = "".join([val.upper() if val.islower() else val.lower() for val in string])
print(y)
>>> 'THe BIG brown fOx jUmpEd OveR THe lazy dOG'
This doesn't use any 'pythonic' methods and gives the answer in a basic logical format using ASCII :
sentence = 'aWESOME is cODING'
words = sentence.split(' ')
sentence = ' '.join(reversed(words))
ans =''
for s in sentence:
if ord(s) >= 97 and ord(s) <= 122:
ans = ans + chr(ord(s) - 32)
elif ord(s) >= 65 and ord(s) <= 90 :
ans = ans + chr(ord(s) + 32)
else :
ans += ' '
print(ans)
So, the output will be : Coding IS Awesome
I am a python newbie, and am struggling for what I thought was a simple code. My instructions are, Write a function that takes one string parameter word and will return the number of vowels in the string.
Also, just for clarification, supercat is my one string parameter word.
I've been working on this code for some time, and it's gotten a little jumbled.
This is what I have so far.
vowelletters = ["A","E","I","O","U","a","e","i","o","u"]
def isVowel(supercat):
if supercat in vowel:
return True
else:
return False
print isVowel(supercat)
def countvowel(supercat):
count = 0
for index in super cat:
if isVowel(vowelletters): count += 1
return count
y = countvowel(super cat)
print(y)
you can first make the string to test lowercase() so that you don't have to check for capital vowels (this make it more efficient). Next you can count() how many times each vowel is in the teststring and make a final sum() to get a total.
vowelletters = ["a","e","i","o","u"]
teststring= "hellO world foo bAr"
count = sum(teststring.lower().count(v) for v in vowelletters)
print count #6
You can place everything in a function to easily reuse the code.
def countVowels(mystring):
vowelletters = ["a","e","i","o","u"]
return sum(mystring.lower().count(v) for v in vowelletters)
Spaces in variable names not allowed, I would say:
for index in super cat:
and
y = countvowel(super cat)
It looks to me as if your indentation has problems and you left an extra space in there. (super cat instead of supercat)
You also used vowelletters instead of index in countvowel() and forgot to use the global statement in isVowel().
vowelletters = ["A","E","I","O","U","a","e","i","o","u"]
def isVowel(supercat):
global vowelletters
if supercat in vowelletters:
return True
else:
return False
print isVowel(supercat) # This isn't executed
# because it is after a return statement.
def countvowel(supercat):
count = 0
for index in supercat:
if isVowel(index): count += 1
return count
y = countvowel("supercat")
print(y)
how about this:
vowelletters = ("a","e","i","o","u")
def countvowel(word):
word = word.lower()
count = 0
for char in word:
if char in vowelletters:
count += 1
return count
print countvowel('super cat') # prints 3
or using the list comprehension:
vowelletters = ("a","e","i","o","u")
def countvowel(word):
word = word.lower()
vowels = [char for char in word if char in vowelletters]
return len(vowels)
You can simplify this function that you're writing
def countvowel(supercat):
count = 0
for i in range(len(supercat)-1):
if supercat[i] in "AEIOUaeiou":
count += 1
print(count)
You can use sum() and a generator.
def countVowels(word):
return sum(1 for c in word if c in "AEIOUaeiou")
print(countVowels('supercat'))