add two integers

[Gishan]

how to add to integers,what is the easiest way to do it?

ui->label2->setText(ui->plainTextEdit->toPlainText());
int A,B,C;
QString S1(ui->label->selectedText());
QString S2(ui->label->selectedText());
A = S1.toInt();
B = S2.toInt();
C = static_cast<int>(A)+ B; //need to add A + B but it gives 0 to me