Question

This is my first C++ program. It prints the number of words in the input.

My first question, how does it go into the loop and add to the count? is it every time i type the space character? if so, how does it know I’m trying to count words?

using namespace std;

int main() {
    int count;
    string s;
    count = 0;
    while (cin >> s)
        count++;
    cout << count << '\n';
    return 0;
}

My second question. Can someone explain to me what namespace std means for a begineer?

Answer 1

1. Cin will capture input until a space, yes. The specific style of loop you have will go until an End-Of-File (EOF) is found or until bad input is provided. That loop doesn’t look like common C++ practice to me, but it’s described here.

2.namespace std is how you tell the compiler where to look to find the objects you’re referencing in your code. Because different objects are “inside” different namespaces, you either have to tell the compiler where they are specifically (aka std::cin) or tell it for convenience where an object you use will be in the future (with using namespace std).