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      std::array<T,N>::data

      From cppreference.com
      <cpp‎ |container‎ |array

      [edit template]
       
       
       
       
      T* data()noexcept;
      (1)(since C++11)
      (constexpr since C++17)
      const T* data()constnoexcept;
      (2)(since C++11)
      (constexpr since C++17)

      Returns a pointer to the underlying array serving as element storage. The pointer is such that range[data()data()+ size()) is always avalid range

      If*this is empty,data() is not dereferenceable.

      Contents

      [edit]Return value

      Pointer to the underlying element storage. For non-empty containers, the returned pointer compares equal to the address of the first element.

      [edit]Complexity

      Constant.

      [edit]Notes

      If*this is empty,data() may or may not return a null pointer.

      [edit]Example

      Run this code
      #include <cstddef>#include <iostream>#include <span>#include <array> void pointer_func(constint* p,std::size_t size){std::cout<<"data = ";for(std::size_t i=0; i< size;++i)std::cout<< p[i]<<' ';std::cout<<'\n';} void span_func(std::span<constint> data)// since C++20{std::cout<<"data = ";for(constint e: data)std::cout<< e<<' ';std::cout<<'\n';} int main(){std::array<int,4> container{1,2,3,4}; // Prefer container.data() over &container[0]    pointer_func(container.data(), container.size()); // std::span is a safer alternative to separated pointer/size.    span_func({container.data(), container.size()});}

      Output:

      data = 1 2 3 4data = 1 2 3 4

      [edit]See also

      access the first element
      (public member function)[edit]
      access the last element
      (public member function)[edit]
      returns the number of elements
      (public member function)[edit]
      access specified element
      (public member function)[edit]
      (C++20)
      a non-owning view over a contiguous sequence of objects
      (class template)[edit]
      (C++17)
      obtains the pointer to the underlying array
      (function template)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/container/array/data&oldid=122713"

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