How to pass a two-dimensional array to a function in C?

Question

My function prototype is

int** rotate(int **arr, int row, int col, int fl);

where arr is the two dimensional array, row<

Answer 1

A pointer to a pointer is different from a pointer to an array. Array-to-pointer decaying can only happen on the left-most side (e.g. int [3][20] to int (*)[20]).

Change your function declaration to

int** rotate(int (*arr)[20], int row, int col, int fl);

or more obviously,

int** rotate(int arr[][20], int row, int col, int fl);

Note you have to fix the size at compile-time.