打印单词列表（向量<string> ) 使用指针</string>

Question

I am trying to print the list of words from a vector of string (query_list) but I can't get it to work. I know that the current code prints the address.

        vector<string>* query_list_ptr;
        query_list_ptr = &query_list;

        for (i = 0; i < num_words; i++) {
            cout << query_list_ptr << " ";
            query_list_ptr++;
        }

I tried the following:

1. I get an error when I tried using "*query_list_ptr" to dereference it at the "cout <<" line.
2. I also get an error when I tried variations of "vector<string>* query_list_ptr" to "vector<string*> query_list_ptr".
3. Another error is "query_list_ptr = query_list" that's why I ended up adding the ampersand to "query_list_ptr = &query_list;".

Thanks for all the help. I could do without pointers but it's for my CS class about pointers.

Answer 1

The pointer to the first element of std::vector can be obtained via the data() member function.

const string* query_list_ptr; // you want to print words, so I guess the pointer should point to string
query_list_ptr = query_list.data(); // get the pointer to the first element

for (i = 0; i < num_words; i++) {
    cout << *query_list_ptr << " "; // dereference the pointer to get the word to print
    query_list_ptr++;
}