如何最好地处理 C/C++ 中的动态多维数组？

在 C 和/或 C++ 中操作动态（所有维度直到运行时才知道）多维数组的可接受/最常用的方法是什么。

我正在尝试找到最简洁的方法来完成此 Java 代码的功能：

public static void main(String[] args){
 Scanner sc=new Scanner(System.in);
 int rows=sc.nextInt();
 int cols=sc.nextInt();
 int[][] data=new int[rows][cols];
 manipulate(data);
}

public static void manipulate(int[][] data){
   for(int i=0;i<data.length;i++)
   for(int j=0;j<data[0].length.j++){
         System.out.print(data[i][j]);       
   }    
}

（从 std_in 读取只是为了澄清尺寸直到运行时才知道）。

编辑：我注意到这个问题很受欢迎，尽管它已经很老了。我实际上并不同意投票最高的答案。我认为 C 的最佳选择是使用一维数组，正如 Guge 在下面所说的“你可以分配行colssizeof(int) 并通过 table[row*cols+col] 访问它。”。

C++ 有多种选择，如果您真的喜欢 boost 或 stl，那么下面的答案可能更好，但最简单且可能最快的选择是使用 C 中的一维数组。

如果您想要 [][] 语法，C 和 C++ 中的另一个可行选择是 lillq 在底部的答案是手动构建具有大量 malloc 的数组。

Use 升压::多数组.

正如在您的示例中一样，您在编译时唯一需要知道的是维度数。这是文档中的第一个示例：

#include "boost/multi_array.hpp"
#include <cassert>

int 
main () {
  // Create a 3D array that is 3 x 4 x 2
  typedef boost::multi_array<double, 3> array_type;
  typedef array_type::index index;
  array_type A(boost::extents[3][4][2]);

  // Assign values to the elements
  int values = 0;
  for(index i = 0; i != 3; ++i) 
    for(index j = 0; j != 4; ++j)
      for(index k = 0; k != 2; ++k)
        A[i][j][k] = values++;

  // Verify values
  int verify = 0;
  for(index i = 0; i != 3; ++i) 
    for(index j = 0; j != 4; ++j)
      for(index k = 0; k != 2; ++k)
        assert(A[i][j][k] == verify++);

  return 0;
}

编辑：根据评论中的建议，这是一个“简单”的例子允许您在运行时定义多维数组大小的应用程序，从控制台输入询问。 以下是此示例应用程序的示例输出（使用表示它是 3 维的常量进行编译）：

Multi-Array test!
Please enter the size of the dimension 0 : 4

Please enter the size of the dimension 1 : 6

Please enter the size of the dimension 2 : 2

Text matrix with 3 dimensions of size (4,6,2) have been created.

Ready!
Type 'help' for the command list.

>read 0.0.0
Text at (0,0,0) :
  ""

>write 0.0.0 "This is a nice test!"
Text "This is a nice test!" written at position (0,0,0)

>read 0.0.0
Text at (0,0,0) :
  "This is a nice test!"

>write 0,0,1 "What a nice day!"
Text "What a nice day!" written at position (0,0,1)

>read 0.0.0
Text at (0,0,0) :
  "This is a nice test!"

>read 0.0.1
Text at (0,0,1) :
  "What a nice day!"

>write 3,5,1 "This is the last text!"
Text "This is the last text!" written at position (3,5,1)

>read 3,5,1
Text at (3,5,1) :
  "This is the last text!"

>exit

代码中的重要部分是主函数，我们从用户那里获取尺寸并使用以下命令创建数组：

const unsigned int DIMENSION_COUNT = 3; // dimension count for this test application, change it at will :)

// here is the type of the multi-dimensional (DIMENSION_COUNT dimensions here) array we want to use
// for this example, it own texts
typedef boost::multi_array< std::string , DIMENSION_COUNT > TextMatrix;

// this provide size/index based position for a TextMatrix entry.
typedef std::tr1::array<TextMatrix::index, DIMENSION_COUNT> Position; // note that it can be a boost::array or a simple array

/*  This function will allow the user to manipulate the created array
    by managing it's commands.
    Returns true if the exit command have been called.
*/
bool process_command( const std::string& entry, TextMatrix& text_matrix );

/* Print the position values in the standard output. */
void display_position( const Position& position );

int main()
{
    std::cout << "Multi-Array test!" << std::endl;

    // get the dimension informations from the user
    Position dimensions; // this array will hold the size of each dimension 

    for( int dimension_idx = 0; dimension_idx < DIMENSION_COUNT; ++dimension_idx )
    {
        std::cout << "Please enter the size of the dimension "<< dimension_idx <<" : ";
        // note that here we should check the type of the entry, but it's a simple example so lets assume we take good numbers
        std::cin >> dimensions[dimension_idx]; 
        std::cout << std::endl;

    }

    // now create the multi-dimensional array with the previously collected informations
    TextMatrix text_matrix( dimensions );

    std::cout << "Text matrix with " << DIMENSION_COUNT << " dimensions of size ";
    display_position( dimensions );
    std::cout << " have been created."<< std::endl;
    std::cout << std::endl;
    std::cout << "Ready!" << std::endl;
    std::cout << "Type 'help' for the command list." << std::endl;
    std::cin.sync();


    // we can now play with it as long as we want
    bool wants_to_exit = false;
    while( !wants_to_exit )
    {
        std::cout << std::endl << ">" ;
        std::tr1::array< char, 256 > entry_buffer; 
        std::cin.getline(entry_buffer.data(), entry_buffer.size());

        const std::string entry( entry_buffer.data() );
        wants_to_exit = process_command( entry, text_matrix );
    }

    return 0;
}

您可以看到，要加入数组中的元素，非常简单：您只需使用operator()，如以下函数所示：

void write_in_text_matrix( TextMatrix& text_matrix, const Position& position, const std::string& text )
{
    text_matrix( position ) = text;
    std::cout << "Text \"" << text << "\" written at position ";
    display_position( position );
    std::cout << std::endl;
}

void read_from_text_matrix( const TextMatrix& text_matrix, const Position& position )
{
    const std::string& text = text_matrix( position );
    std::cout << "Text at ";
    display_position(position);
    std::cout << " : "<< std::endl;
    std::cout << "  \"" << text << "\"" << std::endl;
}

注意：我在 VC9 + SP1 中编译了这个应用程序 - 只得到了一些容易忘记的警告。