huffman coding which will make u encoding

网址：http://deeplearning.stanford.edu/wiki/index.php/Exercise:Sparse_Autoencoder斯坦福深度学习的教程，这个是稀疏编码的的练习，可以直接运行-URL: http://deeplearning.stanford.edu/wiki/index.php/Exercise:Sparse_Autoencoder Stanford deep learning tutorial, this is a sparse coding exer