The following declaration within a definition of your class is not enough: private: static map_type * map; In one .cpp file, you must also add: map_type* BaseFactory::map = NULL; This article might help you too: Static data members (C++ only) + this question, which has almost 100k views by now: Initializing private static members 2 … Read more
You practically already answered your question: Because declaration does not assign a value. Therefore your second sample never makes sense. The first sample consists of two separate statements each of which could make sense in a certain context. Therefore it compiles. 1 solved Why can’t variables be declared and modified at once? (C++)
Even easier than that. Behold the power of uniform initialization: foo({1,2}); solved Is it possible to create temp structs/classes with initializer lists? [closed]
You never call your method “forloop()”, that’s the reason why there’s nothing printed. NewbieJavaDeveloper’s answer is a good one. But if you want to pactice “method and return”, here is another answer: import java.util.Scanner;//import scanner so user can input class arrays { public static void main(String[] param) { String[] animals = arrays(); forloop(animals); System.exit(0); } … Read more
What is the difference between char *exp=”a+b” and char exp[]=”a+b”? Are they stored the same way in memory or they differ? solved What is the difference between char *exp=”a+b” and char exp[]=”a+b”? Are they stored the same way in memory or they differ?
Excellent idea! Here’s a program that prints “hellohello” five times: int i; void print_twice(const std::string& s) { for (i = 0; i < 2; i++) { std::cout << s; } std::cout << std::endl; } int main() { for (i = 0; i < 5; i++) { print_twice(“hello”); } } Or… does it? (Ominous organ music … Read more
You’re hitting undefined behavior for the below line result = result*num; as you’ve not initialized result. The initial value for an uninitialized automatic local variable is indeterminate. Using that invokes UB. Always initialize your local variables, like int count = 0 , result = 0 ; //0 is for illustration, use any value, but do … Read more
A structValue{}; is aggregate initialization, so 0 are guaranteed. As A has no user provided constructor because explicitly defaulted constructors do not count as such, the same applies for value initialization as in A* psstructValue = new A();. For the default initialization cases: Reading uninitialized variables is UB, and Undefined behavior is undefined. The compiler … Read more
In Visual Studio C++, what are the memory allocation representations?: 0xCCCCCCCC : Used by Microsoft’s C++ debugging runtime library to mark uninitialised stack memory At the moment you do obj->, your obj is not initialized. The two lines of code in the question are not your real code, or there is something important taking place … Read more
Well the message is clear and it is easy to spot in your program: double gallons,miles; while (miles>=0||gallons>=0) { miles is declared in a function and so is an automatic variable. Automatic variables are not initialized (so they have garbage values). Now in the first executable statement you compare miles. But miles is still uninitialized. … Read more
To pass literal string to a function, it must have a parameter of type char const *, not char *. So your constructor should have this prototype: Etudiant(char const * c, unsigned int, Date &); Saying the above, you also do not allocate enough memory to copy a string in your constructor. This line: this->name … Read more
yes you can initialize an object without any parameters, let me explain simply, an object is just a copy from a class, it has a copy of all the public methods and fields inside this class. We use objects to access members of a class so let’s assume you have two classes X and Y … Read more
UPDATE FOR THE NEW CLEARER QUESTION: It sees now that I should have added more text to my question. I wanted to know what would be the sequence of execution in case both these statements(1 and 2) are in one single class for the same variable ? You are interessted something like this: private class … Read more
{ x = a; y = b; } is the compound statement of the constructor point( int a = 0, int b = 0 ); Maybe it will be more clear if to rewrite the constructor like point( int a = 0, int b = 0 ) { x = a; y = b; } … Read more
String.valueOf().length() returns 11 because that is the number of digits/characters in the output (i.e. [@936016386 – an address – has 11 characters) solved How do I properly test the char[ ] fields in my custom object for nulls, blanks, or empty? and Why do char[ ] indicate a length of 11?