CODEWITHSUNDEEP
c++arraysdynamic
Abdul Samad
Abdul Samad

Reputation: 5918

creating dynamic array of string c++

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

How can I do that ?

This is my attempt:

#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

What's the error ?

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

Upvotes: 7

Views: 57212

Answers (6)

johnsyweb
johnsyweb

Reputation: 141780

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"));
}

Upvotes: 11

conectionist
conectionist

Reputation: 2914

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]

Upvotes: 0

steve8918
steve8918

Reputation: 1860

I think that should be:

std::cin >> collection[i];

Upvotes: 1

thpatel
thpatel

Reputation: 160

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;
}

Upvotes: 0

Mark Ransom
Mark Ransom

Reputation: 308111

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

Upvotes: 0

rerun
rerun

Reputation: 25495

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

Upvotes: 10

Related Questions