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Two Dimensional Array

It is a collection of data elements of same data type arranged in rows and columns (that is, in two dimensions).

Declaration of Two-Dimensional Array

Type arrayName[numberOfRows][numberOfColumns];

For example,
int Sales[3][5];




Initialization of Two-Dimensional Array

An two-dimensional array can be initialized along with declaration. For two-dimensional array initialization, elements of each row are enclosed within curly braces and separated by commas. All rows are enclosed within curly braces.
int A[4][3] = {{22, 23, 10},
              {15, 25, 13},
              {20, 74, 67},
              {11, 18, 14}};

Referring to Array Elements

To access the elements of a two-dimensional array, we need a pair of indices: one for the row position and one for the column position. The format is as simple as:
name[rowIndex][columnIndex]

Examples:
printf("%d", A[1][2]);      /* print an array element */
A[1][2]=13;         /* assign value to an array element */
scanf("%d", &A[1][2]);       /* input element */

Using Loop to input an Two-Dimensional Array from user

  #include <stdio.h>

  #define MAX_ROWS 10
  #define MAX_COLS 10
  
  int main()
  {
      int array[MAX_ROWS][MAX_COLS];
      int rows, cols;
  
      // Prompt the user to enter the dimensions of the array
      printf("Enter the number of rows (max %d): ", MAX_ROWS);
      scanf("%d", &rows);
      printf("Enter the number of columns (max %d): ", MAX_COLS);
      scanf("%d", &cols);

      // Input loop to populate the array
      printf("Enter elements of the array:\n");
      for (int i = 0; i < rows; i++)
      {
          for (int j = 0; j < cols; j++)
          {
              printf("Enter element at position (%d, %d): ", i + 1, j + 1);
              scanf("%d", &array[i][j]);
          }
      }
  
      // Display the entered 2D array
      printf("\nEntered 2D Array:\n");
      for (int i = 0; i < rows; i++)
      {
          for (int j = 0; j < cols; j++)
          {
              printf("%d ", array[i][j]);
          }
          printf("\n");
      }
  
      return 0;
  }

Output

  Enter the number of rows (max 10): 3
  Enter the number of columns (max 10): 4
  Enter elements of the array:
  Enter element at position (1, 1): 1
  Enter element at position (1, 2): 2
  Enter element at position (1, 3): 3
  Enter element at position (1, 4): 4
  Enter element at position (2, 1): 5
  Enter element at position (2, 2): 6
  Enter element at position (2, 3): 7
  Enter element at position (2, 4): 8
  Enter element at position (3, 1): 9
  Enter element at position (3, 2): 10
  Enter element at position (3, 3): 11
  Enter element at position (3, 4): 12
  
  Entered 2D Array:
  1 2 3 4 
  5 6 7 8 
  9 10 11 12  

Arrays as Parameters

Two-dimensional arrays can be passed as parameters to a function, and they are passed by reference. When declaring a two-dimensional array as a formal parameter, we can omit the size of the first dimension, but not the second; that is, we must specify the number of columns. For example: 
   void print(int A[][3],int n, int m)
In order to pass to this function an array declared as:
   int arr[4][3];
we need to write a call like this:
   print(arr);
Here is a complete example: 

#include <stdio.h>

void input(int matrix[][10], int, int);
void display(int matrix[][10], int, int);

int main()
{
    int r, c;

    int A[10][10];

    printf("Enter number of rows: ");
    scanf("%d", &r);

    printf("Enter number of columns: ");
    scanf("%d", &c);

    input(A, r, c);
    printf("\n");
    display(A, r, c);

    return 0;
}

void input(int matrix[][10], int m, int n)
{
    int i, j;
    for (i = 0; i < m; i++)
    {
        for (j = 0; j < n; j++)
        {
            printf("Enter data in [%d][%d] : ", i, j);
            scanf("%d", &matrix[i][j]);
        }
    }
}

void display(int matrix[][10], int m, int n)
{
    int i, j;
    for (i = 0; i < m; i++)
    {
        for (j = 0; j < n; j++)
        {
            printf("%d\t", matrix[i][j]);
        }
        printf("\n");
    }
}

Output:

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