Sounds like a job for std::copy_if. Define a predicate that keeps track of elements that already have been processed and return false if they have. If you don’t have C++11 support, you can use the clumsily named std::remove_copy_if and invert the logic. This is an untested example: template <typename T> struct NotDuplicate { bool operator()(const … Read more
What is Scope? Scope is the region or section of code where a variable can be accessed. What is a lifetime? Lifetime is the time duration where an object/variable is in a valid state. For, Automatic/Local non-static variables Lifetime is limited to their Scope. In other words, automatic variables are automagically destroyed once the scope({,}) … Read more
If you know the size at compile time, this will do it: //function prototype void do_something(int (&array)[board_width][board_height]); Doing it with void do_something(int array[board_width][board_height]); Will actually pass a pointer to the first sub-array of the two dimensional array (“board_width” is completely ignored, as with the degenerate case of having only one dimension when you have int … Read more
Escape the quotes with backslashes: printf(“She said \”time flies like an arrow, but fruit flies like a banana\”.”); There are special escape characters that you can use in string literals, and these are denoted with a leading backslash.
With C++11 you can now do struct std::tm tm; std::istringstream ss(“16:35:12”); ss >> std::get_time(&tm, “%H:%M:%S”); // or just %T in this case std::time_t time = mktime(&tm); see std::get_time and strftime for reference
You are allowed to cast a standard layout class object address to a pointer to its first member and back by one of the later paragraphs, which is also often done in C: struct A { int x; }; A a; // “px” is guaranteed to point to a.x int *px = (int*) &a; // … Read more
A mere conversion won’t help you here. There’s no compatibility of any kind between 2D array type and pointer-to-pointer type. Such conversion would make no sense. If you really really need to do that, you have to introduce an extra intermediate “row index” array, which will bridge the gap between 2D array semantics and pointer-to-pointer … Read more
Picture is worth a thousand words – try to draw equation f(k) : and you will get such XY graph (X and Y are in logarithmic scale). If computer could represent 32-bit floats without rounding error then for every k we should get zero. But instead error increases with bigger values of k because of … Read more
The problem is that the following piece of code is a definition, not a declaration: std::ostream& operator<<(std::ostream& o, const Complex& Cplx) { return o << Cplx.m_Real << ” i” << Cplx.m_Imaginary; } You can either mark the function above and make it “inline” so that multiple translation units may define it: inline std::ostream& operator<<(std::ostream& o, … Read more
Encoding in C++ is quite a bit complicated. Here is my understanding of it. Every implementation has to support characters from the basic source character set. These include common characters listed in §2.2/1 (§2.3/1 in C++11). These characters should all fit into one char. In addition implementations have to support a way to name other … Read more