Cannot read functor class in any way

Question

Alright, I'm implementing a dynamic 2-dimensional matrix class. For a basis, this is what I have so far:

template <typename Type>
class dyMatrix {
    private:
        Type *mat;

        int lines, columns;
        int length;

        void assimilate (const dyMatrix<Type>& that) {
            lines = that.lines;
            columns = that.columns;

            length = that.length;
        }

    public:
        dyMatrix (int height, int width)
            : lines(height), columns(width), mat(0)
        {
            length = lines * columns;
            mat = new Type[length];
        };

        // ---

        int getLines() {
            return lines;
        };

        int getColumns() {
            return columns;
        };

        int getLength() {
            return length;
        }

        // ---

        Type& operator() (int i, int j) {
            return mat[j * columns + i];
        };

        Type& operator() (int i) {
            return mat[i];
        };

        // ---

        dyMatrix (const dyMatrix<Type>& that) {
            this->assimilate(that);

            // ---

            mat = new Type[length];

            for (int i = 0; i < length; i++) {
                mat[i] = that.mat[i];
            }
        };

        dyMatrix& operator= (const dyMatrix<Type>& that) {
            Type *local_mat = new Type[that.length];

            for (int i = 0; i < that.length; i++) {
                local_mat[i] = that.mat[i];
            }

            // ---

            this->assimilate(that);

            delete[] mat;
            mat = local_mat;

            // ----

            return *this;
        };

        ~dyMatrix() {
            delete mat;
        };
};

My problem is that I've been having some specific problems when trying to read input into it. For example, I have the following main():

int main() {
    int lanes, cols;
    cin >> lanes >> cols;

    dyMatrix<int> map(lanes, cols);

    /* CONTINUE READING */

    cout << endl;
    for (int i = 0; i < lanes; i++) {
        for (int j = 0; j < cols; j++) {
            cout << map(i, j) << ' ';
        }
        cout << endl;
    }
}

Where it is a commented section, if I put the following lines of code:

int aux;
for (int i = 0; i < lanes; i++) {
    for (int j = 0; j < cols; j++) {
        cin >> map(i, j);
    }
}

or:

int aux;
for (int i = 0; i < lanes; i++) {
    for (int j = 0; j < cols; j++) {
        cin >> aux;
        map(i, j) = aux;
    }
}

or even:

int aux;
for (int i = 0; i < lanes; i++) {
    for (int j = 0; j < cols; j++) {
        cin >> aux;
        map(i, j) = i + j; // !!!
    }
}

...It won't work. For some reason, however, the following will:

int aux;
for (int i = 0; i < lanes; i++) {
    for (int j = 0; j < cols; j++) {
        // cin >> aux;
        map(i, j) = i + j; // Still the same thing as before, logically
    }
}

I do not understand. What is happening here?

---

edit: Sorry, forgot to include my debugging procedure.

Input:

3 5
1 2 3 4 5
1 2 3 4 5

The first line has the dimensions of the matrix. The second and third lines are values written into it; After pressing Enter at the end of the third line, however, the program crashes.

It doesn't even work with this input:

3 5
1
2
3
4
5
1
2
3
4
5

It crashes right after the second 5, again.

Answer 1

Your indices appear the wrong way around:

    Type& operator() (int i, int j) {
        return mat[j * columns + i];
    };

Here, i is clearly the column and j is the row. However, in your loops the arguments appear in the opposite order:

for (int i = 0; i < lanes; i++) {
    for (int j = 0; j < cols; j++) {
        map(i, j) = ...; // row then column
    }
}

Also, the destructor should be using delete[] and not delete.