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How can building a heap be O(n) time complexity?
Can someone help explain how can building a heap be O(n) complexity?
17 Answers
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Turning multi-line string into single comma-separated
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You can use awk and sed:
awk -vORS=, '{ print $2 }' file.txt | sed 's/,$/\n/'
Or if you want to use a pipe:
echo "data" | awk -vORS=, '{ print $2 }' | sed 's/,$/\n/'
To break it down:
awk is great at handling data broken down into fields
-vORS=, sets the "output record separa...
PHP: exceptions vs errors?
Maybe I'm missing it somewhere in the PHP manual, but what exactly is the difference between an error and an exception? The only difference that I can see is that errors and exceptions are handled differently. But what causes an exception and what causes an error?
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How do I remedy “The breakpoint will not currently be hit. No symbols have been loaded for this docu
A C# desktop application on the express edition worked, but then it didn't work 5 seconds later.
112 Answers
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cannot download, $GOPATH not set
...icial Go site discusses GOPATH and how to lay out a workspace directory.
export GOPATH="$HOME/your-workspace-dir/" -- run it in your shell, then add it to ~/.bashrc or equivalent so it will be set for you in the future. Go will install packages under src/, bin/, and pkg/, subdirectories there. You'...
Reverse engineering from an APK file to a project
...which I transferred to my phone. Is there a way to reverse the process of exporting an application to the .apk file, so I can get my project back?
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What's the nearest substitute for a function pointer in Java?
...od that's about ten lines of code. I want to create more methods that do exactly the same thing, except for a small calculation that's going to change one line of code. This is a perfect application for passing in a function pointer to replace that one line, but Java doesn't have function pointers...
What are the differences between LDAP and Active Directory?
...swered Mar 19 '09 at 18:26
JohnFxJohnFx
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Mark parameters as NOT nullable in C#/.NET?
...null isn't being used anywhere for it and at run-time throw ArgumentNullException .
6 Answers
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How to schedule a function to run every hour on Flask?
...roundScheduler() from APScheduler package (v3.5.3):
import time
import atexit
from apscheduler.schedulers.background import BackgroundScheduler
def print_date_time():
print(time.strftime("%A, %d. %B %Y %I:%M:%S %p"))
scheduler = BackgroundScheduler()
scheduler.add_job(func=print_date_time,...