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#include <iostream>
#include <cmath>
using namespace std;

// simple matrix multiplication

#define THRESHOLD 2

int nextPowerOfTwo(int n) {
    // return pow(2, int(ceil(log2(n))));
    int power = 1;
    while (power < n) {
        power *= 2;
    }
    return power;
}

class Matrix {
    int rows, cols;
    int view_rows, view_cols;
    int **data;
public:
    Matrix(int r, int c) {
        rows = r;
        cols = c;
        view_rows = r;
        view_cols = c;
        data = new int*[rows];
        for (int i = 0; i < rows; i++) {
            data[i] = new int[cols];
        }
    }
    ~Matrix() {
        for (int i = 0; i < rows; i++) {
            delete [] data[i];
        }
        delete [] data;
    }
    void set(int i, int j, int val) {
        data[i][j] = val;
    }
    int get(int i, int j) {
        return data[i][j];
    }
    int getRows() {
        return view_rows;
    }
    int getCols() {
        return view_cols;
    }
    void setView(int r, int c) {
        view_rows = r;
        view_cols = c;
    }
    void print() {
        for (int i = 0; i < rows; i++) {
            cout << "[";
            for (int j = 0; j < cols; j++) {
                cout << data[i][j] << " ";
            }
            cout << "]" << endl;
        }
    }
};

Matrix* matmul(Matrix *a, Matrix *b) {
    if (a->getCols() != b->getRows()) {
        throw std::invalid_argument("Matrix dimensions do not match.");
    }
    Matrix *c = new Matrix(a->getRows(), b->getCols());
    for (int i = 0; i < a->getRows(); i++) {
        for (int j = 0; j < b->getCols(); j++) {
            int sum = 0;
            for (int k = 0; k < a->getCols(); k++) {
                sum += a->get(i, k) * b->get(k, j);
            }
            c->set(i, j, sum);
        }
    }
    return c;
}

// pad matrix
Matrix* pad(Matrix *a, int new_rows, int new_cols) {
    Matrix *padded = new Matrix(new_rows, new_cols);
    for (int i = 0; i < new_rows; i++) {
        for (int j = 0; j < new_cols; j++) {
            if (i < a->getRows() && j < a->getCols()) {
                padded->set(i, j, a->get(i, j));
            } else {
                padded->set(i, j, 0);
            }
        }
    }
}

// split matrix
void split_matrix(Matrix *a, Matrix *a11, Matrix *a12, Matrix *a21, Matrix *a22, int new_size) {
    for (int i = 0; i < new_size; i++) {
        for (int j = 0; j < new_size; j++) {
            a11->set(i, j, a->get(i, j));
            a12->set(i, j, a->get(i, j + new_size));
            a21->set(i, j, a->get(i + new_size, j));
            a22->set(i, j, a->get(i + new_size, j + new_size));
        }
    }
}

// merge matrix
void merge_matrix(Matrix *a, Matrix *a11, Matrix *a12, Matrix *a21, Matrix *a22, int big_size, int small_size) {
    for (int i = 0; i < small_size; i++) {
        for (int j = 0; j < small_size; j++) {
            a->set(i, j, a11->get(i, j));
            a->set(i, j + small_size, a12->get(i, j));
            a->set(i + small_size, j, a21->get(i, j));
            a->set(i + small_size, j + small_size, a22->get(i, j));
        }
    }
}

// add matrix
Matrix* add(Matrix *a, Matrix *b, int n) {
    Matrix *c = new Matrix(n, n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            c->set(i, j, a->get(i, j) + b->get(i, j));
        }
    }
    return c;
}

// subtract matrix
Matrix* sub(Matrix *a, Matrix *b, int n) {
    Matrix *c = new Matrix(n, n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            c->set(i, j, a->get(i, j) - b->get(i, j));
        }
    }
    return c;
}

Matrix* strassen(Matrix *a, Matrix *b) {

}

int main() {
    const int A_ROWS = 16;
    const int A_COLS = 32;
    const int B_ROWS = 32;
    const int B_COLS = 48;

    Matrix *a = new Matrix(A_ROWS, A_COLS);
    Matrix *b = new Matrix(B_ROWS, B_COLS);

    // same seed
    srand(2);

    // init randomly
    for (int i = 0; i < A_ROWS; i++) {
        for (int j = 0; j < A_COLS; j++) {
            a->set(i, j, rand() % 10);
        }
    }
    for (int i = 0; i < B_ROWS; i++) {
        for (int j = 0; j < B_COLS; j++) {
            b->set(i, j, rand() % 10);
        }
    }

    cout << "Main:" << endl;

    cout << "Matrix A:" << endl;
    a->print();

    cout << "Matrix B:" << endl;
    b->print();

    Matrix *c_normal = matmul(a, b);
    cout << "Matrix C normal:" << endl;
    c_normal->print();


    Matrix *c_strassen = strassen(a, b);
    cout << "Matrix C strassen:" << endl;
    c_strassen->print();

    return 0;
}