// This is a single-line comment in C++. It begins with // and extends to the end of the line.
int main() {
// This is a comment within a function.
// It provides a brief explanation of the purpose of the code that follows.
int x = 5; // This comment explains the initialization of the variable 'x' with the value 5.
int y = 10; // Similarly, this comment explains the initialization of the variable 'y' with the value 10.
// The following line calculates the sum of x and y.
int sum = x + y;
return 0; // Indicates the successful execution of the program.
}