How to populate a vector upon construction of object in C++? -

i trying create class has member of type std::vector , want vector filled number 2 when instance of class created:

#include <vector> using namespace std; class primes{    private:      vector <int> myvec;      myvec.push_back(2); }; 

but compiler gives me:

error: ‘myvec’ not name type

class primes{    private:      vector <int> myvec;      myvec.push_back(2);   // <-- can not placed here }; 

compiler expects there declaration / definition of member or method (member function). can not place there code such myvec.push_back(2);. must placed inside body of method:

class primes { private:     std::vector<int> myvec;  public:     void addprime(int num) {         myvec.push_back(num);     } }; 

or in case want construct instance of primes vector contain number 2:

class primes { public:     primes() : myvec(std::vector<int>(1, 2)) { }  private:     std::vector<int> myvec; }; 

or if need populate vector more of them:

int primes[] = { 1, 2, 3, 5, 7 }; const int pcount = sizeof(primes) / sizeof(primes[0]);  class primes { public:     primes()      : myvec(std::vector<int>(primes, primes + pcount)) { }  private:     std::vector<int> myvec; };