lec.1
https://drive.google.com/file/d/1v3PCQGMNzpucD2TkIO5LUfhtBBTGpC7A/view?usp=sharing
lec.2
https://drive.google.com/file/d/1-6jbI4OUNIuTYodPuLLic8xgcFdQl0Ie/view?usp=sharing
lec.3
https://drive.google.com/file/d/1ol960PtVTVNw-vIuuXX70tod7OF89z_0/view?usp=sharing
lec.4
https://drive.google.com/file/d/1bv1J7hgW9LDSWuHf_4h-CM8hOMDYNsbG/view?usp=sharing
lec.5
https://drive.google.com/file/d/1H65XS8GngFqAtKLNR_Mx_PXeqaCIy_cX/view?usp=sharing