std::string s("Hello world");
for (char & c : s)
{
std::cout << "One character: " << c << "\n";
c = '*';
}
Here is what the above code is Doing:
1. It creates a string object s with the value "Hello world".
2. It creates a reference to a character c.
3. It loops over all the characters in s.
4. It prints the current character.
5. It replaces the current character with an asterisk.
QString str1 = “1234.56”; double val = str1.toFloat(); // val == 1234.56 Here is what the above code is Doing: 1. The first line creates a QString object called str1 and initializes it with the string “1234.56”. 2. The second line converts the string to a double and stores the result in the variable val….
if (m.count(key)) // key exists Here is what the above code is Doing: 1. Create a map m. 2. Insert a key-value pair into m. 3. Check if a key exists in m.
// Make sure the members appear in the initializer list in the same order as they appear in the class Class C { int a; int b; C():b(1),a(2){} //warning, should be C():a(2),b(1) } // or you can turn -Wno-reorder Here is what the above code is Doing: 1. The class C has two members, a…
/* *You need to top and tail your header file with an include guard, * in order to avoid calling the header file twice (Once in header of child * class, once in main). In order to have header specificy, it’s best to * derive the name from the name of the class. */ #ifndef…
/** * int output = QMessageBox::icon(this, tr(“Title”), tr(“content”), * QMessageBox::button, QMessageBox::defaultButton); */ //for example : int ret = QMessageBox::warning(this, tr(“My Application”), tr(“The document has been modified.\n” “Do you want to save your changes?”), QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel, QMessageBox::Save); Here is what the above code is Doing: 1. The first argument is the parent widget….
#include #include using namespace std; int main () { ofstream myfile; myfile.open (“file.txt”); myfile