Method dfs

contents/huffman_encoding/code/rust/huffman.rs:113–127

(&self, code: String, codebook: &mut HashMap<char, String>)

    }

    fn dfs(&self, code: String, codebook: &mut HashMap<char, String>) {
        match *self {
            HuffmanTree::Branch {
                ref left,
                ref right,
                ..
            } => {
                left.dfs(code.clone() + "0", codebook);
                right.dfs(code.clone() + "1", codebook);
            }
            HuffmanTree::Leaf { value, .. } => {
                codebook.insert(value, code);
            }
        }
    }
}

impl Codebook {