Number is a fractional number. Only effective on NUMA systems. Requires parent cgroups be set and cannot be higher than parent. Also check rtprio ulimits.
Try it out — write in any initial value for x and y: It almost seems like magic — the the same statement is repeated 3 times and voila — the values magically swap?
How it works To understand this trick, break the statements into unique values: I want to understand it deep down and have it make sense, not be some artifact of the properties of XOR.
So, this is exactly what we do on line 2. We XOR the hybrid with y, which cancels out all the y information, leaving us only with x.
We save this result back into y, so now they have swapped. On the last line, x still has the hybrid value. This leaves us with y, and the swap is complete! Would you really use this? Let me show you why: Suppose x and y are pointers or references to objects, and both point to the same location.
Well, take a look at what happens if we expand out line 1: So x becomes 0 right at the get-go. So, would you have caught this bug? Cute tricks like these can be pretty dangerous. As Brian Kernighan said: Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.
This applies so well here — we wrote the code pretty much as cleverly as we could: So, treat this as an intellectual exercise that brings up a few points: XOR is a great way to combine information and later extract it.
XOR-based encryption uses this technique. Also, XOR can combine N items together, not just 2. There are new ways to perform even the simplest operations. Even more hairy details Now, how does this work on a CPU-level?
For example, if you add 3 to a register in machine-language pseudocode: So, we used the ALU as temporary scratch space before we had the final answer.
Some machines have a 1-step exchange XCHG instruction to swap two registers.Most people would swap two variables x and y using a temporary variable, like this: tmp = x x = y y = tmp Here’s a neat programming trick to swap two values without needing a temp.
Given two variables, x and y, swap two variables without using a third variable. Method 1 (Using Arithmetic Operators) The idea is to get sum in one of the two given numbers.
Java is Pass-by-Value, Dammit! Introduction. I finally decided to write up a little something about Java's parameter passing. I'm really tired of hearing folks (incorrectly) state "primitives are passed by value, objects are passed by reference". 8.
Write a c program to check given string is palindrome number or not. 7. Write a c program to solve quadratic equation. 8.
Write a c program . Sources. For most Unix systems, you must download and compile the source code. The same source code archive can also be used to build the Windows and Mac versions, and is the starting point for ports to all other platforms. Purpose The purpose of this C++11 FAQ is To give an overview of the new facilities (language features and standard libraries) offered by C++11 in addition to what is .