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Smart pointers: who owns the object? [closed]

...ct that must be accessible from objects nested in it (usually as a virtual base class). This could be solved by passing a weak_ptr to them, but it doesn't have a shared_ptr to itself. As it knows these objects wouldn't live longer than him, it passes a hub_ptr to them (it's just a template wrapper t...
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Moving decimal places over in a double

...ass, we were asked in general what numbers can be exactly represented in a base. For base=p1^n1*p2^n2... you can represent any N where N=n*p1^m1*p2^m2. Let base=14=2^1*7^1... you can represent 1/7 1/14 1/28 1/49 but not 1/3 I know about financial software -- I converted Ticketmaster's financial r...
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How can I multiply and divide using only bit shifting and adding?

... = 21 * 5 (Same as initial expression) (_2 means base 2) As you can see, multiplication can be decomposed into adding and shifting and back again. This is also why multiplication takes longer than bit shifts or adding - it's O(n^2) rather than O(n) in the number of bits. R...
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How to redirect cin and cout to files?

...cout("output.txt"); // optional performance optimizations ios_base::sync_with_stdio(false); std::cin.tie(0); std::cin.rdbuf(cin.rdbuf()); std::cout.rdbuf(cout.rdbuf()); func(); } Note that ios_base::sync_with_stdio also resets std::cin.rdbuf. So the order matters. S...
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How can I avoid running ActiveRecord callbacks?

... that also works while creating an object class Person < ActiveRecord::Base attr_accessor :skip_some_callbacks before_validation :do_something after_validation :do_something_else skip_callback :validation, :before, :do_something, if: :skip_some_callbacks skip_callback :validation, :a...
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Best practices to handle routes for STI subclasses in rails

...45908, using this method will enable you to use "form_for". ActiveRecord::Base#becomes share | improve this answer | follow | ...
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Benefits of EBS vs. instance-store (and vice-versa) [closed]

...can still fail - not a silver bullet Keep in mind that any piece of cloud-based infrastructure can fail at any time. Plan your infrastructure accordingly. While EBS-backed instances provide certain level of durability compared to ephemeral storage instances, they can and do fail. Have an AMI fro...
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How to check if an activity is the last one in the activity stack for an application?

... Hope this will help new beginners, Based above answers which works for me fine, i am also sharing code snippet so it will be easy to implement. solution : i used isTaskRoot() which return true if current activity is only activity in your stack and other than ...
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How to make a always full screen?

...t;/div> Tested to work in Firefox, Chrome, Opera, Vivaldi, IE7+ (based on emulation in IE11). share | improve this answer | follow | ...
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How to avoid scientific notation for large numbers in JavaScript?

...ive BigInt (note: not Leemon's) should be available; Chromium and browsers based on it (Chrome, the new Edge [v79+], Brave) and Firefox all have support; Safari's support is underway. Here's how you'd use BigInt for it: BigInt(n).toString() Example: const n = 13523563246234613317632; console...