I'm new to Stack Overflow and Python.
I am trying to build a word by replacing items in a list by index and when I run this code only the first instance is replace.
word = "DRIPPING"
letter = "P"
checkList = [" _ "] * len(word)
letterLocation=[3,4]
for (index, replacement) in zip(letterLocation, letter):
checkList[index] = replacement
print(checkList)
Returns [' _ ', ' _ ', ' _ ', 'P', ' _ ', ' _ ', ' _ ', ' _ ']
Any help will be very welcome.
zip takes two or more iterables, and generates tuples that contain an element from each iterable until one of the iterables is exhausted.
Since letter contains only one character, zip will thus emit only a single tuple:
>>> list(zip(checkList,letter))
[(' _ ', 'P')]
You do not need zip here, you can simply iterate over the checkList, and assign letter to all these indices:
for index in letterLocation: # look ma, no zip
checkList[index] = letter
Related
I have to write an application that asks the user to enter a list of numbers separated by a space and then prints the sum of the numbers. The user can enter any number of numbers. I am not allowed to use the split function in python. I was wondering how I can do it that. Any help would be appreciated it as I'm kind of stuck on where to start.
Possible solution is to use regular expressions:
# import regular expression library
import re
# let user enter numbers and store user data into 'data' variable
data = input("Enter numbers separated by space: ")
"""
regular expression pattern '\d+' means the following:
'\d' - any number character,
'+' - one or more occurence of the character
're.findall' will find all occurrences of regular expression pattern
and store to list like '['1', '258', '475', '2', '6']'
please note that list items stored as str type
"""
numbers = re.findall(r'\d+', data)
"""
list comprehension '[int(_) for _ in numbers]' converts
list items to int type
'sum()' - summarizes list items
"""
summary = sum([int(_) for _ in numbers])
print(f'Sum: {summary}')
Another solution is following:
string = input("Enter numbers separated by space: ")
splits = []
pos = -1
last_pos = -1
while ' ' in string[pos + 1:]:
pos = string.index(' ', pos + 1)
splits.append(string[last_pos + 1:pos])
last_pos = pos
splits.append(string[last_pos + 1:])
summary = sum([int(_) for _ in filter(None, splits)])
print(f'Sum: {summary}')
From my point of view, the first option is more concise and better protected from user errors.
I am doing an hangman game in python and I'm stuck in the part where I have a random generated word and I'm trying to hide the word by replacing all characters with dashes like this:
generated word -> 'abcd'
hide word -> _ _ _ _
I have done the following:
string = 'luis'
print (string.replace ((string[i]) for i in range (0, len (string)), '_'))
And it gives me the following error:
^
SyntaxError: Generator expression must be parenthesized
Please give me some types
You could try a very simple approach, like this:
word = "luis"
print("_" * len(word))
Output would be:
>>> word = "luis"
>>> print("_" * len(word))
____
>>> word = "hi"
>>> print("_" * len(word))
__
The simplest is:
string = "luis"
"_" * len(string)
# '____'
If you want spaces inbetween:
" ".join("_" * len(string))
# '_ _ _ _'
However, since you will need to show guessed chars later on, you are better off starting with a generator in the first place:
" ".join("_" for char in string)
# '_ _ _ _'
So that you can easily insert guessed characters:
guessed = set("eis")
" ".join(char if char in guessed else "_" for char in string)
# '_ _ i s'
I'm writing a program to play the game hangman, and I don't think I'm using my global variable correctly.
Once the first iteration of the program concludes after a correct guess, any successive iteration with a correct guess prints the word and all of its past values.
How can I only print the most current value of word? This chunk of code is within a while loop where each iteration gets user input. Thanks!
Code:
word=''
#lettersGuessed is a list of string values of letters guessed
def getGuessedWord(secretWord, lettersGuessed):
global word
for letter in secretWord:
if letter not in lettersGuessed:
word=word+' _'
elif letter in lettersGuessed:
word=word+' '+letter
return print(word)
The Output:
#first iteration if 'a' was guessed:
a _ _ _ _
#second iteration if 'l' was guessed:
a _ _ _ _ a _ _ l _
#third iteration if 'e' was guessed:
a _ _ _ _ a _ _ l _ a _ _ l e
#Assuming the above, for the third iteration I want:
a _ _ l e
Note: This is only a short section of my code, but I don't feel like the other chunks are relevant.
The main problem you are facing is that you are appending your global variable every time you call your function. However, I think you don't need to use a global variable, in general this is a very bad practice, you can simply use the following code considering what you are explaining in your question:
def getGuessedWord(secretWord, lettersGuessed):
return ' '.join(letter if letter in lettersGuessed else '_'
for letter in secretWord)
I also think that it is better if you use a python comprehension to make your code faster.
every time you are calling the function getGuessedWord you are adding to `word, You can not use a global:
secretWord = "myword"
def getGuessedWord(secretWord, lettersGuessed):
word = ""
for letter in secretWord:
if letter not in lettersGuessed:
word=word+' _'
elif letter in lettersGuessed:
word=word+' '+letter
return print(word)
getGuessedWord(secretWord,"")
getGuessedWord(secretWord,"m")
getGuessedWord(secretWord,"mwd")
Or you can solve this by setting word at a constant length, (not as nice and harder to follow) e.g: word='_ '*len(secretWord), then instead of adding to it, replace the letter word=word[:2*i]+letter +word[2*i+1:]
Example here:
secretWord = "myword"
word='_ '*len(secretWord)
def getGuessedWord(secretWord, lettersGuessed):
global word
for i, letter in enumerate(secretWord):
if letter in lettersGuessed:
word=word[:2*i]+letter +word[2*i+1:]
return print(word)
getGuessedWord(secretWord,"")
getGuessedWord(secretWord,"m")
getGuessedWord(secretWord,"w")
getGuessedWord(secretWord,"d")
I'm trying to reverse the words in a string individually so the words are still in order however just reversed such as "hi my name is" with output "ih ym eman si" however the whole string gets flipped
r = 0
def readReverse(): #creates the function
start = default_timer() #initiates a timer
r = len(n.split()) #n is the users input
if len(n) == 0:
return n
else:
return n[0] + readReverse(n[::-1])
duration = default_timer() - start
print(str(r) + " with a runtime of " + str(duration))
print(readReverse(n))
First split the string into words, punctuation and whitespace with a regular expression similar to this. Then you can use a generator expression to reverse each word individually and finally join them together with str.join.
import re
text = "Hello, I'm a string!"
split_text = re.findall(r"[\w']+|[^\w]", text)
reversed_text = ''.join(word[::-1] for word in split_text)
print(reversed_text)
Output:
olleH, m'I a gnirts!
If you want to ignore the punctuation you can omit the regular expression and just split the string:
text = "Hello, I'm a string!"
reversed_text = ' '.join(word[::-1] for word in text.split())
However, the commas, exclamation marks, etc. will then be a part of the words.
,olleH m'I a !gnirts
Here's the recursive version:
def read_reverse(text):
idx = text.find(' ') # Find index of next space character.
if idx == -1: # No more spaces left.
return text[::-1]
else: # Split off the first word and reverse it and recurse.
return text[:idx][::-1] + ' ' + read_reverse(text[idx+1:])
If my string is this: 'this is a string', how can I produce all possible combinations by joining each word with its neighboring word?
What this output would look like:
this is a string
thisis a string
thisisa string
thisisastring
thisis astring
this isa string
this isastring
this is astring
What I have tried:
s = 'this is a string'.split()
for i, l in enumerate(s):
''.join(s[0:i])+' '.join(s[i:])
This produces:
'this is a string'
'thisis a string'
'thisisa string'
'thisisastring'
I realize I need to change the s[0:i] part because it's statically anchored at 0 but I don't know how to move to the next word is while still including this in the output.
A simpler (and 3x faster than the accepted answer) way to use itertools product:
s = 'this is a string'
s2 = s.replace('%', '%%').replace(' ', '%s')
for i in itertools.product((' ', ''), repeat=s.count(' ')):
print(s2 % i)
You can also use itertools.product():
import itertools
s = 'this is a string'
words = s.split()
for t in itertools.product(range(len('01')), repeat=len(words)-1):
print(''.join([words[i]+t[i]*' ' for i in range(len(t))])+words[-1])
Well, it took me a little longer than I expected... this is actually tricker than I thought :)
The main idea:
The number of spaces when you split the string is the length or the split array - 1. In our example there are 3 spaces:
'this is a string'
^ ^ ^
We'll take a binary representation of all the options to have/not have either one of the spaces, so in our case it'll be:
000
001
011
100
101
...
and for each option we'll generate the sentence respectively, where 111 represents all 3 spaces: 'this is a string' and 000 represents no-space at all: 'thisisastring'
def binaries(n):
res = []
for x in range(n ** 2 - 1):
tmp = bin(x)
res.append(tmp.replace('0b', '').zfill(n))
return res
def generate(arr, bins):
res = []
for bin in bins:
tmp = arr[0]
i = 1
for digit in list(bin):
if digit == '1':
tmp = tmp + " " + arr[i]
else:
tmp = tmp + arr[i]
i += 1
res.append(tmp)
return res
def combinations(string):
s = string.split(' ')
bins = binaries(len(s) - 1)
res = generate(s, bins)
return res
print combinations('this is a string')
# ['thisisastring', 'thisisa string', 'thisis astring', 'thisis a string', 'this isastring', 'this isa string', 'this is astring', 'this is a string']
UPDATE:
I now see that Amadan thought of the same idea - kudos for being quicker than me to think about! Great minds think alike ;)
The easiest is to do it recursively.
Terminating condition: Schrödinger join of a single element list is that word.
Recurring condition: say that L is the Schrödinger join of all the words but the first. Then the Schrödinger join of the list consists of all elements from L with the first word directly prepended, and all elements from L with the first word prepended with an intervening space.
(Assuming you are missing thisis astring by accident. If it is deliberately, I am sure I have no idea what the question is :P )
Another, non-recursive way you can do it is to enumerate all numbers from 0 to 2^(number of words - 1) - 1, then use the binary representation of each number as a selector whether or not a space needs to be present. So, for example, the abovementioned thisis astring corresponds to 0b010, for "nospace, space, nospace".