Vectors are much like arrays, but they vary in size.
/*
 * Read some integers into an vector, then echo them.
 */
#include <iostream>
#include <vector>
int main()
{
        // Read them in.
        std::vector<int> vec;
        std::cout << "Enter some integers: " << std::endl;
        int val;
        while(std::cin >> val) {
                vec.push_back(val);
        }
        // Print them back out again.
        std::cout << "===============" << std::endl;
        for(int sub = 0; sub < vec.size(); ++sub)
                std::cout << vec[sub] << " ";
        std::cout << std::endl;
}
Textbook: pp. 362—371
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