void iter(node * root, std::string key, std::map<std::string, std::string> &dictionary){

if(root == NULL){
    return;
}

if(root->data != '\0') {
    std::string s{root->data};
    dictionary[key] = s;
}

iter(root->left, key+"0", dictionary);
iter(root->right, key+"1", dictionary);
}

void decode_huff(node * root, string s) {
std::map<std::string, std::string> dictionary;   
std::string binary = "";

iter(root, binary, dictionary);

binary="";

for (char c : s){
    std::string str{c};
    binary = binary+str;

    if (dictionary.find(binary) != dictionary.end()) {
        std::cout <<dictionary[binary];
        binary="";
    }
}
}