C++ Array name from variable

Question

I would like to get some help with c++. Im trying to change the array name using value from variable. something like this:

global variables:

string array1[5][5];
string array2[5][5];

in a function:

string var;
if (option1) { var = "array1"; }
if (option2) { var = "array2"; }
var[1][1]="some data";

unfortunately this does not work. is there any way to manage the arrays like this?

M.M · Accepted Answer · 2015-12-02 03:30:05Z

2

Yes, you can use a pointer:

decltype(array1) *ptr{};

if ( option1 )       ptr = &array1;
else if ( option2 )  ptr = &array2;

if ( ptr )
    (*ptr)[1][1] = "some data";

answered Dec 2, 2015 at 3:30

M.M

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Comments

songyuanyao · Accepted Answer · 2015-12-02 03:28:46Z

1

No, you can't. You should

string array1[5][5];
string array2[5][5];

string (*var)[5];
if (option1) { var = array1; }
if (option2) { var = array2; }
var[1][1]="some data";

answered Dec 2, 2015 at 3:28

songyuanyao

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Stack Exchange Broke The Law · Accepted Answer · 2015-12-02 03:22:02Z

1

No, there isn't.

You could use another level of array indexing:

string array[2][5][5];

int var;
if(option1) {var = 0;}
if(option2) {var = 1;}
array[var][1][1] = "some data";

answered Dec 2, 2015 at 3:22

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