I have the following code

template <size_t size_x, size_t size_y>
void product(int (&arr)[size_x][size_y],int (&arr1)[size_x][size_y])
{
   for (int i=0;i<size_x;i  )
   for (int j=0;j<size_y;j  )
   {
     cout << "The size of a1[][] is" << arr[i][j] << endl;
   }


   for (int i=0;i<size_x;i  )
   for (int j=0;j<size_y;j  )
   {
     cout << "The size of a1[][] is" << arr1[i][j] << endl;
   }
}

int main()
{

    int A[2][2] = { { 1, 2 }, { 3, 4 }};
    int B[2][2] = { { 0, 5}, { 6, 7 } };

    product(A,B);
    return 0;
}

I am trying to pass arrays to a function. However this program works fine if the arrays are of equal dimension. I want to pass arrays with different dimensions. How can I pass an array of 22 and 32 array to a function?

CodePudding user response：

How can I pass an array of 22 and 32 array to a function?

This can be done simply by providing extra template parameters

template <size_t size_x1, size_t size_y1, size_t size_x2, size_t size_y2>
void product(int (&arr)[size_x1][size_y1],int (&arr1)[size_x2][size_y2]);

Demo

CodePudding user response：

Starting with C 20 you can use auto as type for function parameters:

void product(auto &arr, auto &arr1)

You can get the array sizes with std::size(arr) for the first index and std::size(*arr) for the second index.

Complete program:

#include <iostream>

using namespace std;

void product(auto &arr, auto &arr1)
{
   for (const auto &inner: arr)
   for (const auto &elem: inner)
   {
     cout << "arr[][] is " << elem << endl;
   }


   for (const auto &inner: arr1)
   for (const auto &elem: inner)
   {
     cout << "arr1[][] is " << elem << endl;
   }

   cout << "size of arr " << size(arr) << " * " << size(*arr) << endl;
   cout << "size of arr " << size(arr1) << " * " << size(*arr1) << endl;
}

int main()
{
    int A[2][2] = { { 1, 2 }, { 3, 4 }};
    int B[3][1] = { { 0}, { 6 }, {3} };

    product(A,B);
    return 0;
}

https://godbolt.org/z/7a315erhf