Question

I want to allocate variable sized 2D array in a function without using new operator such that this 2D array is available to other functions in the same file.

    void draw(int i)
    {   size=i;   }

    void assign(char symbol)
    {
        char one[size][size];
        /// ... Assigning values to one  ...
    }
    void display()
    {   /// Displaying values of one[size][size]
        for(int i=0;i<size;i++)
        {
            for(int j=0;j<size;j++)
            cout<<one[i][j];
            cout<<endl;
        }
    }

Execution order of functions is draw -> assign -> display

This question may have been asked earlier.
But my problem is..
-> I can’t declare the array outside assign function globally because value of size is not known.
-> I can’t use “one” array in “display” function because its scope is limited to “assign” function.

And I also don’t want to use either new or malloc operators.
Please help if there is any alternative available.

Answer 1

C++ doesn’t support stack-allocated Variable Length Arrays like for example C99. You should use std::vector<T> instead. If you really want to use stack allocation you can use alloca().