"cast with the appropriate bitmask" while using alternative cout - c++

Question

So I decided to make a console class as an alternative to std::cout << stream << std::endl routine.
Here's my code:
class Console {
public:
Console() {
this->console = GetStdHandle(STD_OUTPUT_HANDLE);
this->current_color = 7;
}
void color(int k) {
this->current_color = k;
SetConsoleTextAttribute(this->console, this->current_color);
}
void remove() {
FreeConsole();
}
void print(std::string s) {
std::cout << s;
}
void log(std::string s) {
this->color(7);
std::cout << s << std::endl;
this->color(this->current_color);
}
void error(std::string s) {
this->color(12);
std::cout << s << std::endl;
this->color(this->current_color);
}
private:
HANDLE console;
int current_color;
};
Initializing console as Console console;, I use console.log("String " + n), where n is an unsigned short, for example. The code compiles fine, however this thing shows up:
What is it and how do I fix it?

Answer 1

Your program contains undefined behavior.
console.log("String " + n) (where n is an integral type) is interpreted as follows:
const char* tmp_ptr1 = "String ";
const char* tmp_ptr2 = tmp_ptr1 + n;
console.log(std::string(tmp_ptr2));
If n > 7 or n < 0 the code above performs out-of-bounds access. In your case this access happens to pick up some other (sub)string from the string literals linked into your program's data section and you see it on your screen. In theory anything else could happen.