2D array passed in function prototype

Question

Here is my code in c++.

void multTable(int arr[][], int maxNum);

Before the main method, I declared this function prototype and then defined it after the main method towards the bottom of my code. However, I get an error stating that multidimensional array must have bounds for all dimensions. I don't understand how I can fix this.

What is `maxNum` ? Is it related to array dimension ? – Jarod42 Dec 23 '13 at 03:46 — Jarod42, Dec 23 '13 at 03:46

Fiddling Bits · Accepted Answer · 2017-01-11T15:25:16.760

4

If your 2D arrays will have a fixed column size. You can do this:

void multTable(int arr[][MAX_COLS], int maxNum);

You'll have to call it like this:

#define MAX_ROWS (5)
#define MAX_COLS (7)

int arr[MAX_ROWS][MAX_COLS] = {...};
multTable(arr, 7);

edited Jan 11 '17 at 15:25

answered Dec 23 '13 at 03:19

Fiddling Bits

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I get an error that says use of parameters 'rows' and 'col' outside function body. – ruthless Dec 23 '13 at 03:27
1

@user2548635 Sorry, I made a mistake. I edited my answer accordingly. – Fiddling Bits Dec 23 '13 at 03:41

score 1 · Answer 2 · answered Dec 23 '13 at 03:29

1

You may use this prototype:

template <int ROW, int COLUMN>
void multTable(int (&arr)[ROW][COLUMN], int maxNum);

answered Dec 23 '13 at 03:29

Jarod42

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score 1 · Answer 3 · answered Dec 23 '13 at 03:29

You have to provide the second dimension of the array. Otherwise the compiler could not dereference your pointer. That's why your compiler is generating an error

#define N 10 // just an exemple

void multTable(int arr[][N], int maxNum); // N is the 2nd dimention

2D array passed in function prototype

3 Answers3