How to pass a 2D array to a pointer in C

Mastering 2D Array Pointer Passing in C: Step-by-Step Tutorial

There are two ways to pass a 2D array to a pointer in C:

• Passing the entire array as a pointer: This is the simplest way to pass a 2D array to a pointer. To do this, simply declare the function parameter as a pointer to the type of the array. For example, to pass a 2D array of integers, you would declare the function parameter as int **array.

• Passing the base address of the array as a pointer: This is a more efficient way to pass a 2D array to a pointer, but it is also more complex. To do this, you need to cast the name of the array to a pointer to the type of the array. For example, to pass a 2D array of integers, you would cast the name of the array to a pointer to an array of integers, like this: (int (*)[2])array.

How to catch a 2D array passed to a pointer in C

Once you have passed a 2D array to a function as a pointer, you can catch it in the function by declaring the function parameter as a pointer to the type of the array. For example, to catch a 2D array of integers, you would declare the function parameter as int **array.

How to print a 2D array passed to a pointer in C

To print a 2D array that has been passed to a function as a pointer, you can use a nested for loop to iterate over the array and print each element. For example, to print a 2D array of integers, you would use the following code:

void print_2d_array(int **array, int rows, int cols) {
  for (int i = 0; i < rows; i++) {
    for (int j = 0; j < cols; j++) {
      printf("%d ", array[i][j]);
    }
    printf("\n");
  }
}

Example code

How to pass a 2D array to a pointer, catch it in the function, and print it:

#include<stdio.h>
void print_2d_array(int **array, int rows, int cols) {
  for (int i = 0; i < rows; i++) {
    for (int j = 0; j < cols; j++) {
      printf("%d ", array[i][j]);
    }
    printf("\n");
  }
}

int main() {
  int array[2][2] = {{1, 2}, {3, 4}};

  print_2d_array(array, 2, 2);

  return 0;
}

Output:

1 2
3 4