C RUBY-ON-RAILS MYSQL ASP.NET DEVELOPMENT RUBY .NET LINUX SQL-SERVER REGEX WINDOWS ALGORITHM ECLIPSE VISUAL-STUDIO STRING SVN PERFORMANCE APACHE-FLEX UNIT-TESTING SECURITY LINQ UNIX MATH EMAIL OOP LANGUAGE-AGNOSTIC VB6 MSBUILD

# Struggling with simple reverse function

## Struggling with simple reverse function Tag : python , By : Lathentar Date : January 11 2021, 03:34 PM

Hope that helps For the list of arbitrary length l assuming that we want to keep head and tail of int(l/3) and reverse the middle.
``````l = len(s); n = int(l/3)
ls[:n] + ls[-n-1:n-1:-1] + ls[-n:]
``````

 No Comments Right Now !

Share :

## Simple function to reverse a list

Tag : python , By : Ram
Date : March 29 2020, 07:55 AM
To fix the issue you can do list.append appends an item to the list in place and returns nothing (= return None), unlike + operator which return new list concatenating two lists:
``````>>> [1, 2] + [3]
[1, 2, 3]
>>> [1, 2].append(3) # => None
>>>
``````
``````>>> lst = [1,2]
>>> lst.append([3,4])
>>> lst
[1, 2, [3, 4]] # <--- Is this what you want?

>>> lst = [1,2]
>>> lst.extend([3,4])
>>> lst
[1, 2, 3, 4]
``````
``````def revFromEnd2(L):
if len(L)==1:
return L
else:
ret = [L[-1]]
ret.extend(revFromEnd2(L[:-1]))
return ret
``````

## Struggling with maths... How to reverse calculate a percentage?

Tag : php , By : Kirks
Date : March 29 2020, 07:55 AM
wish of those help I believe this is a language agnostic question and more focused on math, however I prefer PHP. I know how to calculate percentages the normal (forward) way: , You can do
``````1,083,000 * 100 / 54.15
``````
``````\$x = \$result * 100 / \$percent
``````

## Struggling to get a simple function running from command line

Tag : python , By : inquiringmind
Date : March 29 2020, 07:55 AM
wish help you to fix your issue There are two problems:
You're opening the file in write mode. This deletes all the contents of the file. Drop the "w" parameter. You can't add strings (as read from the file) to an integer. You need to convert them to integers first: sum += int(i)

## Struggling to see why reverse sort doesnt take into account 100

Tag : python , By : Blight
Date : March 29 2020, 07:55 AM
Any of those help Everything you read from a file is read as a string. You need to convert the numbers to ints before using them to compare as you expect. You can accomplish this by just changing the following line:
``````scores.sort(key=lambda x: int(x[1]))
``````

## Struggling to reverse decryption algorithm in C

Tag : c , By : littlefuzz
Date : March 29 2020, 07:55 AM
I wish this helpful for you This is my first ever question on StackOverflow so if I do something wrong don't go too hard on me. Anyways, I have found a certain encryption in a C file I was looking in and I have the decryption code but I have no clue on how to reverse it so I can encrypt my own string into it. , It's straight forward: Decrypt is - 3 so encrypt is + 3
Decrypt
``````#include <stdio.h>

int main(void) {
int r;
char str[] = {"4:;145;14;81583"};
for(r = 0; (r < 100 && str[r] != '\0'); r++)
str[r] = str[r] - 3;
//      ^ notice: minus
printf("%s\n", str);
return 0;
}
``````
``````178.128.185.250
``````
``````include <stdio.h>

int main(void) {
int r;
char str[] = {"178.128.185.250"};
for(r = 0; (r < 100 && str[r] != '\0'); r++)
str[r] = str[r] + 3;
//      ^ notice: plus
printf("%s\n", str);
return 0;
}
``````
``````4:;145;14;81583
``````
``````for(r = 0; (r < 100 && str[r] != '\0'); r++)
``````
``````for(r = 0; str[r] != '\0'; r++)
``````