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Get the length of a String
...0;, Snail 🐌, Penguin 🐧, Dromedary 🐪"
println("unusualMenagerie has \(count(unusualMenagerie)) characters")
// prints "unusualMenagerie has 40 characters"
right from the Apple Swift Guide
(note, for versions of Swift earlier than 1.2, this would be countElements...
How to overload the operator++ in two different ways for postfix a++ and prefix ++a?
...plement postfix in terms of prefix.
//
Number operator++ (int) // postfix ++
{
Number result(*this); // make a copy for result
++(*this); // Now use the prefix version to do the work
return result; // return the copy ...
What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
...
Example without declaring it static:
public class Variable
{
public int i = 5;
public void test()
{
i = i + 5;
Console.WriteLine(i);
}
}
public class Exercise
{
static void Main()
{
Variable var = new Variable();
var.test();
Variab...
Linq list of lists to single list
...
Here is a sample code for you:
List<int> listA = new List<int> { 1, 2, 3, 4, 5, 6 };
List<int> listB = new List<int> { 11, 12, 13, 14, 15, 16 };
List<List<int>> listOfLists = new List<List<int>> { listA, listB };
...
Reverse engineering from an APK file to a project
...an unknown APK file.
Download dex2jar tool from dex2jar.
Use the tool to convert the APK file to JAR:
$ d2j-dex2jar.bat demo.apk
dex2jar demo.apk -> ./demo-dex2jar.jar
Once the JAR file is generated, use JD-GUI to open the JAR file. You will see the Java files.
The output will be similar to...
How to elegantly check if a number is within a range?
...
There are a lot of options:
int x = 30;
if (Enumerable.Range(1,100).Contains(x))
//true
if (x >= 1 && x <= 100)
//true
Also, check out this SO post for regex options.
...
Java String - See if a string contains only numbers and not letters
...ontains only numerics.
If you actually want to use the numeric value, use Integer.parseInt() or Double.parseDouble() as others have explained below.
As a side note, it's generally considered bad practice to compare boolean values to true or false. Just use if (condition) or if (!condition).
...
How to fix “Incorrect string value” errors?
...
The table and fields have the wrong encoding; however, you can convert them to UTF-8.
ALTER TABLE logtest CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;
ALTER TABLE logtest DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;
ALTER TABLE logtest CHANGE title title VARCHAR(100) ...
What is the C++ function to raise a number to a power?
...e <cmath> header has these overloads:
pow(float, float);
pow(float, int);
pow(double, double); // taken over from C
pow(double, int);
pow(long double, long double);
pow(long double, int);
Now you can't just do
pow(2, N)
with N being an int, because it doesn't know which of float, double...
How does a garbage collector avoid an infinite loop here?
...ion running. The main thread completes effectively right away, at which point the finalizer thread simply runs as many times as it gets a chance to before the process gets torn down. Nothing is keeping the program alive.
s...