Unless you wrap your entire menu code inside a loop and make the exit condition for this loop the user input(in your case typing 5 for exit) the program will terminate as soon as it returns from your seatingchart() function because the list() function will return to main(i.e seatingchart() returns to list() and list() will … Read more
First, you will need to push your prime numbers in the vector. At the beginning, unless you ask otherwise, the vector is empty. You can push a prime number using this snippet: // somewhere you declare your vector std::vector<unsigned long long> primes; // code computing a prime number unsigned long long prime; …. // Push … Read more
Speaking generally, neither is “faster”. They do the same thing, in the same way. Speaking even more generally, if you really want to know, measure it on your system. Speaking as generally as I possibly can, try not to care about things like this.
Show some research effort when you post a question here. #include <iostream> #include <unordered_set> #include <fstream> int main() { std::unordered_set<std::string> mySet; std::string word; std::ifstream file1(“myFile1.txt”); if(file1.is_open()) { while(file1 >> word) mySet.emplace(word); file1.close(); } std::ifstream file2(“myFile2.txt”); if(file2.is_open()) { while(file2 >> word) { auto look = mySet.find(word); if(look != mySet.cend()) mySet.erase(look); } file2.close(); } std::ofstream outputFile(“Out.txt”); if(outputFile.is_open()) … Read more
Firstly, a common mistake in reading 8.5.3p5 is to miss that it has two top level bullet points. You may have accidentally misread the final occurence of “Otherwise” as a third bullet point – but it is in fact a subpart of the second bullet point (also starting Otherwise). char a=”a”; char* p = &a; … Read more
this[j] is hardly ever the right thing to do. It can only be correct, if *this happens to be a subobject within an array, and have at least j siblings after it. this[j] is equivalent to *(this + j). As you can see, it dereferences a pointer to jth sibling after *this. I suspect, that … Read more
If you are puzzled about the dots here is what they are: %.1lf is the format specification for precision. This is requesting one digit after the decimal point in the printf output. The 1. and 2. in (a*1.+b)/2. mean that those literals are double (as opposed to 1 that would be int and 1.f that … Read more
Strictly speaking, the behavior is undefined: 6.5 Expressions … 2 If a side effect on a scalar object is unsequenced relative to either a different side effect on the same scalar object or a value computation using the value of the same scalar object, the behavior is undefined. If there are multiple allowable orderings of the … Read more
template <typename T1, typename T2> class Parent { protected: T1 _data1; T2 _data2; public: Parent(T1 init_data1, T2 init_data2) : _data1(init_data1), _data2(init_data2) { std::cout << “Parent created” << std::endl; } virtual ~Parent() { std::cout << “Parent deleted” << std::endl; } virtual T2 multiple() = 0; }; template <typename T1, typename T2> class Child : public Parent<T1, … Read more
You can avoid a circular include problem by using a forward declaration of a class instead of an #include: #ifndef ENTRANCE_H #define ENTRANCE_H #include <vector> #include “Diodio.h” class Segment; class Entrance { public: Entrance(); ~Entrance(); void operate(); protected: Segment *givesEntryTo; std::vector<Diodio> elBooths; std::vector<Diodio> manBooths; private: }; #endif // ENTRANCE_H (Entrance.cpp may or may not need … Read more