Small Steps VI — Growing into C++

Meeting standard strings and arrays

Meet standard strings and arrays.

What you will learn

A container holds several values. std::string and std::vector are standard tools corresponding to the strings and arrays you know.

Try it

void small_main()
{
    std::string text = "Hello";
    std::vector<int> numbers = {3, 7, 2, 9};

    print(text);
    print("Characters: ", text.size());
    print("Numbers: ", numbers.size());
    print("First number: ", numbers[0]);
}

The length operation is named size() instead of length(). The example prints Hello, Characters: 5, Numbers: 4, and First number: 3.

Bracket positions still start at 0. Do not expect standard containers' [] to report out-of-range errors the way Small does.

Exercise

Create a std::vector<int> containing 5 and 10, add another value with push_back(15), and print them all.

void small_main()
{
    std::vector<int> numbers = {5, 10};

    // Add 15 and print every value.
}

Hint

Use a range-based for such as for (int value : numbers) to visit every value.

void small_main()
{
    std::vector<int> numbers = {5, 10};
    numbers.push_back(15);

    for (int value : numbers)
        print(value);
}