How to print 2D Arrays in C++?

Question

I am trying to print a text file out on screen using arrays, but I\'m not sure why it does not appear the way it is in the text file.

The text file:

Answer 1

It is not only mistake that you miss the "endl". The program will also skip the first line in the source file because of calling the function discard_line(reg), so you only can get the others data(5 6 7 8). It is not necessary to use the function at all. in addition, make sure that you init the array and check boundary of array, such as MAX_SIZE, to guarantee the input data not to overflow the array.

Answer 2

you can do it like this

#include <iostream>

int your_array[2][4] = { 
  {1,2,3,4}, 
  {5,6,7,8}  
};

using namespace std;

int main() {

    // get array columns and rows
      int rows =  sizeof your_array / sizeof your_array[0]; 
      int cols = sizeof your_array[0] / sizeof(int); 
      
      // Print 2d Array
     cout << "your_array data "<<endl<<endl;
    for (int i = 0; i < rows; ++i)
    {
        for (int j = 0; j < cols; ++j)
        {
            std::cout << your_array[i][j] << std::endl;
        }
     //   std::cout << std::endl;
    }

}

output

1
2
3
4
5
6
7
8

Answer 3

You are printing std::endl after each number. If you want to have 1 row per line, then you should print std::endl after each row. Example:

#include <iostream>

int main(void)
{
    int myArray[][4] = { {1,2,3,4}, {5,6,7,8} };
    int width = 4, height = 2;

    for (int i = 0; i < height; ++i)
    {
        for (int j = 0; j < width; ++j)
        {
            std::cout << myArray[i][j] << ' ';
        }
        std::cout << std::endl;
    }
}

Also note that writing using namespace std; at the beginning of your files is considered bad practice since it causes some of user-defined names (of types, functions, etc.) to become ambiguous. If you want to avoid exhausting prefixing with std::, use using namespace std; within small scopes so that other functions and other files are not affected.