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What is the performance cost of having a virtual method in a C++ class?
Having at least one virtual method in a C++ class (or any of its parent classes) means that the class will have a virtual table, and every instance will have a virtual pointer.
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Do you use NULL or 0 (zero) for pointers in C++?
In the early days of C++ when it was bolted on top of C, you could not use NULL as it was defined as (void*)0 . You could not assign NULL to any pointer other than void* , which made it kind of useless. Back in those days, it was accepted that you used 0 (zero) for null pointers.
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What is Gradle in Android Studio?
Gradle is a bit confusing to me, and also for any new Android developer. Can anyone explain what Gradle in Android Studio is and what its purpose is? Why is it included in Android Studio?
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How to get the current branch name in Git?
...om a Subversion background and, when I had a branch, I knew what I was working on with "These working files point to this branch".
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map vs. hash_map in C++
I have a question with hash_map and map in C++. I understand that map is in STL, but hash_map is not a standard. What's the difference between the two?
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PostgreSQL: How to pass parameters from command line?
I have a somewhat detailed query in a script that uses ? placeholders. I wanted to test this same query directly from the psql command line (outside the script). I want to avoid going in and replacing all the ? with actual values, instead I'd like to pass the arguments after the query.
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ASP.NET MVC: What is the purpose of @section? [closed]
...tion, I saw this blog article .
The author ScottGu adds @section to the Index.cshtml.
4 Answers
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How to determine the number of days in a month in SQL Server?
I need to determine the number of days in a month for a given date in SQL Server.
28 Answers
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Read file line by line using ifstream in C++
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First, make an ifstream:
#include <fstream>
std::ifstream infile("thefile.txt");
The two standard methods are:
Assume that every line consists of two numbers and read token by token:
int a, b;
while (infile >> a >> b)
{
// p...
What are the effects of exceptions on performance in Java?
Question: Is exception handling in Java actually slow?
18 Answers
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