char* get_char_code(huffman_tree* ht, char c){
    if(!ht->rght && !ht->lft){
        if(ht->node->symbols[0] == c){
            char* null = (char*)malloc(sizeof(char));
            *null = '\0';
            return null;
        }
        return NULL;
    }
    char* code = get_char_code(ht->rght, c);
    char* new_code = NULL;
    if(!code){
        code = get_char_code(ht->lft, c);
            if(code){
                new_code = (char*)malloc(2*sizeof(char)+strlen(code)*sizeof(char));
                sprintf(new_code, "0%s", code);
            }
    }else{
        int tam = 0;
        if(code) {
            tam = strlen(code);
        }
        new_code = (char*)malloc(2*sizeof(char)+tam*sizeof(char));
        sprintf(new_code, "1%s", code);
    }
    free(code);
    return new_code;
}