c++11 - C++ Iterator with hasNext and Next -

i new c++ world , need help. problem try implement structure hash pair array, there key , data. in structure have nested structure iterator methods hasnext , next. because can not see array (this array in parent) nested structure need pass through constructor, there error ": cannot convert from...", problem pass _array in method getiterator. code below. me? thanks

#pragma once template<typename t, typename u, int size, int(*hashfunction)(t)> struct hashpairpole {  // pair - key - data struct par {     // key     t _first;     // data     u _second;     // list collision records     par* _overflow;      par(t t, u u) {         _first = t;         _second = u;         _overflow = nullptr;     } };   hashparovepole() {}  // static array save data par* _array[size];  // add record hash table void add(t t, u u) {     // calculating of index          par* prvek;     int idx = hashfunction(t) % size;      // element saved in _array[idx], if free, else     //saved list (->_overflow)     prvek = new par(t, u);      if (_array[idx] == nullptr) {         _array[idx] = prvek;     }     else {         prvek->_overflow = _array[idx];     }     _array[idx] = prvek; }  // data hash tabule u& get(t t) {     int idx = hashfunction(t) % size;     par * prvni = _array[idx];      while (prvni->_overflow != nullptr) {         if (prvni->_first == t) {             return prvni->_second;         }         prvni = prvni->_overflow;     }  }  u& operator[](t t) {     return get(t); }  u operator[](t t) const {     const u temp = get(t);     return temp; }  // iterator walking hash table struct iterator {     par* index[size];     par* pompar;     int temp = 0;      iterator(par * _array) {         index = _array;         pompar = index[0];     }      bool hasnext()const {         return pompar != nullptr;     }       std::pair<t, u> next() {         std::pair<t, u> data;         if (hasnext()) {             data.first = pompar->_first;             data.second = pompar->_second;             pompar = pompar->_overflow;         }         temp++;         pompar = index[temp];         return data;     } };     // vytvori iterator    iterator getiterator() {        return iterator(_array);    }  }; 

as far see, problem in line:

par* _array[size]; 

here declare array of size size of pointers par structures, not want.

later try pass array constructor iterator(par * _array), accepts pointer par structure, impossible.

i fix code in following way:

par _array[size]; // instead of par* _array[size]                   // need array of structures instead of array of pointers ... par* index; // instead of par* index[size]             // here looks index pointer current element ... pompar = index; // instead of pompar = index[0];                 // pointer node, while index[0] value 

also, consider using std::vector instead of raw pointers. handle memory management issues you.