C++ contacts handler program with own dynamic template vector class -

i working on project have university. want simple contants program, goal is, can add many names, want, furthermore many properties each names want. every proberty has header, (e.g.:"name") , value (e.g.:"jane").

i have did it, included stl vector class, ought without stl libraries, have written own. of course, isn't working now, program freezes, before can begin. in connection error, have found "a_row" class has been called twice during program have no idea why.

i apoligise copying here lot rows, have been searching problem 3 days nobody find problem, around me. here code, have simplified it, :)

the vector class:

#include <iostream> #include <string>  template <class t> class vector{     t* my_array;     unsigned int vector_size; public:     vector():vector_size(0){}     ~vector(){         delete[] my_array;     } vector(const vector& rhs){     vector_size = rhs.size();     my_array = new t[vector_size];     for(unsigned int i=0;i<vector_size;i++) my_array[i] = rhs[i]; } t& operator[](unsigned int i) {return my_array[i];} const t& operator[](unsigned int i) const {return my_array[i];}  vector& operator=(const vector& rhs){     if (&rhs!=this){         delete[] my_array;         vector_size = rhs.size();         my_array = new t[vector_size];         for(unsigned int i=0;i<vector_size;i++) my_array[i] = rhs[i];     }     return *this; }  void push_back(const t& rhs){     t* tmp = new t[vector_size+1];     for(unsigned int i=0;i<vector_size;i++)         tmp[i] = my_array[i];     tmp[vector_size] = rhs;     delete[] my_array;     my_array = tmp;     vector_size++; }  unsigned int size() const{return vector_size;}  void erase(unsigned int x){     if (vector_size>0){         t* tmp = new t[vector_size-1];         unsigned int counter = 0;         (unsigned int i=0;i<vector_size;i++){             if (i!=x) {                 tmp[counter++] = my_array[i];             }         }         delete[] my_array;         my_array = tmp;         vector_size--;     } } }; 

here classes of contacts program:

class a_row{     std::string header;     std::string value; public:     a_row(const std::string& h="no name",const std::string& v="no "):header(h),value(v){}      std::string geth() const{return header;}     std::string getv() const{return value;}  };  class a_name_card{     vector<a_row> properties; public:     a_name_card(const std::string& f1="no name",const std::string& e1="no name"){         properties.push_back(a_row(f1,e1));     }      unsigned int size()const{return properties.size();}      a_row& get_a_row(int i){return properties[i];}      void add(const std::string& f1="no name",const std::string& e1="no name"){         properties.push_back(a_row(f1,e1));     }  };  class list_of_name_cards{     vector<a_name_card> array_of_names; public:     a_name_card& operator[](int i){return array_of_names[i];}      void add(const std::string& f1="no name", const std::string& e1="no name"){         array_of_names.push_back(a_name_card(f1,e1));     }      unsigned int size() const{return array_of_names.size();} }; 

and here simple main program:

int main(){     list_of_name_cards names;     names.add("name","jane");     return 0; } 

i appreciate kind of helps , again if you've read it.

p.s.: sorry english english not mother tongue.

you need initialize variables:

vector():vector_size(0){} 

what my_array?

vector():my_array(nullptr), vector_size(0){}