A basic Matrix class

matrix.h

#ifndef DP2__MATRIX_H
#define DP2__MATRIX_H

#include <algorithm>
#include <cstdio>
#include <memory>
#include <stdexcept>

template <typename T>
class Matrix {
private:
  size_t row{};
  size_t col{};
  std::unique_ptr<T[]> data;
  void boundscheck(int r, int c) const {
    if (!(0 <= r && r < row && 0 <= c && c < col)) {
      throw std::out_of_range("Can not access out of bound element!");
    }
  }
public:
  // Set all the values of the Matrix
  void setValues(T value) {
    std::fill_n(data.get(), row*col, value);
  }
  explicit Matrix(size_t row, size_t col, T def) {
    // Create a matrix of row X col and initialize
    // each element of the matrix with def
    this->row = row;
    this->col = col;
    this->data = std::make_unique<T[]>(this->row * this->col);
    setValues(def);
  }
  // Overload the [] operator for the 2d array like access
  T* operator[](int r) {
    return &this->data[r * col];
  }
  const T* operator[](int r) const {
    return &this->data[r * col];
  }
  T& at(int r, int c) {
    boundscheck(r, c);
    return this->data[r * col + c];
  }
  const T& at(int r, int c) const {
    boundscheck(r, c);
    return this->data[r * col + c];
  }
  // Overload the << operator for console logging
  friend std::ostream& operator<< (std::ostream& os, Matrix &mObj) {
    auto shape = mObj.shape();
    for(int i=0; i< shape.first; i++) {
      for(int j=0; j<shape.second; j++) {
        os << mObj[i][j] << " ";
      }
      os << "\n";
    }
    return os;
  }
  // Get row and col values
  std::pair<size_t, size_t> shape() const {
    return std::make_pair(this->row, this->col);
  }
};
#endif //DP2__MATRIX_H