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Why is address zero used for the null pointer?
...emory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use if (p != 0) all the time to make sure passed pointers are valid, etc.
...
Is background-color:none valid CSS?
...nswered Jan 5 '12 at 8:42
James AllardiceJames Allardice
152k2121 gold badges309309 silver badges301301 bronze badges
...
Black transparent overlay on image hover with only CSS?
...0; left:0;
background:rgba(0,0,0,0.6);
opacity: 0;
transition: all 1s;
-webkit-transition: all 1s;
}
Use an opacity of 1 when hovering over the pseudo element in order to facilitate the transition:
.image:hover:after {
opacity: 1;
}
END RESULT HERE
If you want to add text on h...
C++ cout hex values?
...
This seems to change all future output from cout to hex; so if you only want 'a' to be printed in hex you may want something like cout << hex << a << dec; to change it back.
– ShreevatsaR
M...
What is the 'dynamic' type in C# 4.0 used for?
C# 4.0 introduced a new type called 'dynamic'. It all sounds good, but what would a programmer use it for?
10 Answers
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How do you calculate log base 2 in Java for integers?
...ting-point to help with integer arithmetics, you have to be careful.
I usually try to avoid FP calculations whenever possible.
Floating-point operations are not exact. You can never know for sure what will (int)(Math.log(65536)/Math.log(2)) evaluate to. For example, Math.ceil(Math.log(1<<29...
How do I toggle an element's class in pure JavaScript?
... Thank you so much! It's working now :) I add more option for loop: var All = document.querySelectorAll('.menu'); for (var i = 0; i < All.length; i++){ All[i].classList.toggle('hidden-phone'); }
– Blue Tram
Feb 1 '19 at 3:52
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Is std::vector so much slower than plain arrays?
...d the array only once. Note: when you resize() the vector you are not only allocating the memory but also running through the vector and calling the constructor on each member.
Re-Arranging the code slightly so that the vector only initializes each object once:
std::vector<Pixel> pixels(di...
Very slow compile times on Visual Studio 2005
...t half-way down the page):
In decreasing order of speedup:
Install Microsoft hotfix 935225.
Install Microsoft hotfix 947315.
Use a true multicore processor (ie. an Intel Core Duo 2; not a Pentium 4 HT).
Use 3 parallel builds. In Visual Studio 2005, you will find the option in Tool...
How to deal with IntelliJ IDEA project files under Git source control constantly changing?
...trol:
.ipr file based format
Share the project .ipr file and and all the .iml module files, don't
share the .iws file as it stores user specific settings.
.idea directory based format
Share all the files under .idea directory in the project root except
the workspace.xml and t...