C++ IntArray

IntArray

• int 자료형을 여러개 담을 수 있는 컨테이너

  #include <iostream>
  
  class IntArray
  {
      int*        data_ = nullptr;
      unsigned    length_ = 0;
  
  public:
      IntArray(unsigned length = 0)
      {
          initialize(length);
      }
  
      IntArray(const std::initializer_list<int>& list)
      {
          initialize(list.size());
          int count = 0;
          for (auto& e : list)
              data_[count++] = e;
      }
  
      ~IntArray()
      {
          delete[] data_;
      }
  
      void    initialize(unsigned length)
      {
          length_ = length;
          if (length_ > 0)
              data_ = new int[length_];
      }
  
      void    reset()
      {
          if (data_)
          {
              delete[] data_;
              data_ = nullptr;
          }
          length_ = 0;
      }
  
      void    resize(const unsigned& length)
      {
          if (length == 0)
              reset();
          else if (length_ < length)
          {
              int* new_data_ = new int[length];
              for (unsigned i = 0; i < length_; ++i)
                  new_data_[i] = data_[i];
              delete[] data_;
              data_ = new_data_;
          }
          length_ = length;
      }
  
      void    insertBefore(const int& value, const int& ix)
      {
          resize(length_ + 1);
          for (int i = length_ - 2; i >= ix; --i)
              data_[i + 1] = data_[i];
          data_[ix] = value;
      }
  
      void    remove(const int& ix)
      {
          for (int i = ix; i < length_ - 1; ++i)
              data_[i] = data_[i + 1];
          --length_;
          if (length_ <= 0)
              reset();
      }
  
      void    push_back(const int& value)
      {
          insertBefore(value, length_);
      }
  
      friend std::ostream& operator << (std::ostream& out, const IntArray& arr)
      {
          for (unsigned i = 0; i < arr.length_; ++i)
              out << arr.data_[i] << ' ';
          return out;
      }
  };
  
  int        main()
  {
      using namespace std;
  
      IntArray my_arr{ 1, 3, 5, 7, 9 };
      cout << my_arr << endl;
  
      my_arr.insertBefore(10, 1);
      cout << my_arr << endl;
  
      my_arr.remove(3);
      cout << my_arr << endl;
  
      my_arr.push_back(13);
      cout << my_arr << endl;
  }
  
  /* stdout
  1 3 5 7 9
  1 10 3 5 7 9
  1 10 3 7 9
  1 10 3 7 9 13
  */