current community

your communities

more stack exchange communities

Stack Exchange
tour help
stack overflow careers
Take the 2-minute tour ×
Stack Overflow is a question and answer site for professional and enthusiast programmers. It's 100% free.
up vote 4 down vote favorite

I am struct to a very basic question. i want to create dynamically an array of string in c++.

How can i do that

#include <iostream>
#include <string>
int main(){
    unsigned int wordsCollection = 6;
    unsigned int length = 6;

    std::string *collection = new std::string[wordsCollection];
    for(unsigned int i = 0; i < wordsCollection; ++i){
        std::cin>>wordsCollection[i];
    }
    return 0;

}

but it giving the following error "error C2109: subscript requires array or pointer type"

wats the error?

And also if am getting input number from user from std::cin can i create an array of that size statically?

share|improve this question
1  
In the future please select your code block and use the {} button; this will make your code show up properly in the question. –  Mark Ransom Jan 20 '12 at 22:27
1  
You typed wordsCollection[i] instead of collection[i]. You can't use a size obtained dynamically (e.g. through std::cin) to create a static array. Also, the array is leaking since you never release it. –  R. Martinho Fernandes Jan 20 '12 at 22:30

6 Answers 6

up vote 6 down vote accepted

You meant to type:

std::cin>>collection[i];

And you also need to delete[] collection (or you'll leak this memory).

It would be better use std::vector<std::string> collection; and avoid the raw pointer usage altogether:

#include <iterator>
#include <iostream>
#include <string>
#include <vector>

int main()
{
    const unsigned int wordsCollection = 6;

    std::vector<std::string> collection;
    std::string word;
    for (unsigned int i = 0; i < wordsCollection; ++i)
    {
        std::cin >> word;
        collection.push_back(word);
    }

    std::copy(collection.begin(),
              collection.end(),
              std::ostream_iterator<std::string>(std::cout, "\n"));
}
share|improve this answer
up vote 9 down vote

use std::vector<string> or std::list<string> over hand rolling it.

share|improve this answer
2  
But the real problem is that wordsCollection should be collection. –  cnicutar Jan 20 '12 at 22:28
    
Oh my God how silly i am... Any how thanks... can you tell me the answer for my second question that can i create a static array of that –  Abdul Samad Jan 20 '12 at 22:31
1  
I agree, but if you choose to go ahead with new std::string do not forget to delete[] collection when you are done. It is a good idea to ensure that for every new you have a delete –  Lea Hayes Jan 20 '12 at 22:31
    
You can't create an array of any size where you get the size at runtime. You can create a pointer to a buffer of n elements that acts like an array but you will have to delete it. Thats one of the many reason using the stl containers are preferable. –  rerun Jan 20 '12 at 22:37
up vote 1 down vote

I think that should be:

std::cin >> collection[i];
share|improve this answer
up vote 0 down vote

I think it's a simple typo. std::cin>>wordsCollection[i] should be std::cin>>collection[i].

share|improve this answer
up vote 0 down vote

Try the following:

#include <vector>
#include <string>
#include <iostream>

int main(int argc, char* argv[])
{
    std::vector<std::string> myStrings;
    myStrings.push_back(std::string("string1"));
    myStrings.push_back(std::string("string2"));

    std::vector<std::string>::iterator iter = myStrings.begin();
    std::vector<std::string>::iterator end = myStrings.end();
    while(iter != end)
    {
        std::cout << (*iter) << std::endl;
        ++iter;
    }
    return 0;
}
share|improve this answer
up vote 0 down vote

You're getting this error because you're trying access the elements of an int (i.e. wordsCollection), not an array of int (i.e. collection). What you should be writing is

std::cin>>collection[i]
share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.