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How dangerous is it to compare floating point values?
...th scanf or strtod, do not exist as floating point values and get silently converted to the nearest approximation. This is what demon9733's answer was talking about.
The fact that many results get rounded due to not having enough precision to represent the actual result. An easy example where you ca...
How do you round a number to two decimal places in C#?
...per to specify the type of rounding (Round-to-even or Away-from-zero). The Convert.ToInt32() method and its variations use round-to-even. The Ceiling() and Floor() methods are related.
You can round with custom numeric formatting as well.
Note that Decimal.Round() uses a different method than Mat...
Parsing command-line arguments in C?
...clude <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
bool isCaseInsensitive = false;
int opt;
enum { CHARACTER_MODE, WORD_MODE, LINE_MODE } mode = CHARACTER_MODE;
while ((opt = getopt(argc, argv, "ilw")) != -1) {
switc...
How to sum up elements of a C++ vector?
...
Actually there are quite a few methods.
int sum_of_elems = 0;
C++03
Classic for loop:
for(std::vector<int>::iterator it = vector.begin(); it != vector.end(); ++it)
sum_of_elems += *it;
Using a standard algorithm:
#include <numeric>
sum_o...
For i = 0, why is (i += i++) equal to 0?
...
This:
int i = 0;
i += i++
Can be seen as you doing (the following is a gross oversimplification):
int i = 0;
i = i + i; // i=0 because the ++ is a postfix operator and hasn't been executed
i + 1; // Note that you are discarding ...
Can we have functions inside functions in C++?
... C++17), you can have functions inside functions in the form of a lambda:
int main() {
// This declares a lambda, which can be called just like a function
auto print_message = [](std::string message)
{
std::cout << message << "\n";
};
// Prints "Hello!" 1...
What's the difference between size_t and int in C++?
...xamples I see a use of the type size_t where I would have used a simple int . What's the difference, and why size_t should be better?
...
Scrollview vertical and horizontal in android
...ends ScrollView {
public VScroll(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public VScroll(Context context, AttributeSet attrs) {
super(context, attrs);
}
public VScroll(Context context) {
super(context);
...
PHP - iterate on string characters
...
Step 1: convert the string to an array using the str_split function
$array = str_split($your_string);
Step 2: loop through the newly created array
foreach ($array as $char) {
echo $char;
}
You can check the PHP docs for more in...
How do I use extern to share variables between source files?
... is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only define it once within a given scope.
A variable defin...