How do I convert std::chrono to int

Question

I have been trying to make a wpm counter and, long story short, am running into an issue: After using the high resolution clock, I need to divide it by 12, but I can't convert std::chrono to int. Here is my code:

#include <iostream>
#include <chrono>
#include <Windows.h>
#include <synchapi.h>

using namespace std;
using namespace std::chrono;
int main()
{
    typedef std::chrono::high_resolution_clock Time;
    typedef std::chrono::seconds s;

    string text;
    string ctext = "One two three four five six seven eight nine ten eleven twelve";

    cout << "Type: "<< ctext << " in" << "\n" << "5" << endl;
    Sleep(1000);
    cout << "4" << endl;
    Sleep(1000);
    cout << "3" << endl;
    Sleep(1000);
    cout << "2" << endl;
    Sleep(1000);
    cout << "1" << endl;
    Sleep(1000);
    cout << "GO" << endl;

    auto start = Time::now();
    cin >> text;
    auto stop = Time::now();

    float wpm = stop - start / 12;
    
    if (ctext == text)
    {
        cout << "Correct! WPM: " << wpm;
    }
    else
    {
        cout << "You had some errors. Your WPM: " << wpm;
    }
}

Are there any alternative methods I could also use to using std::chrono for this?

Does this answer your question? https://stackoverflow.com/questions/2808398/easily-measure-elapsed-time — 463035818_is_not_an_ai, Dec 20 '21 at 11:53
`start` and `stop` are two timepoint, the result of `stop - start` is a `std::chrono::duration`, so, `(stop - start).count()` should give you an integer. — Yves, Dec 20 '21 at 11:55
As you are using `std::chrono`, I suggest to use [`std::this_thread::sleep_for(1s)`](https://en.cppreference.com/w/cpp/thread/sleep_for) instead of `Sleep(1000)`. — Jarod42, Dec 20 '21 at 12:01

Howard Hinnant · Accepted Answer · 2021-12-21T03:15:46.243

std::chrono will elegantly do this problem with a few minor changes...

Instead of Sleep(1000);, prefer this_thread::sleep_for(1s);. You'll need the header <thread> for this instead of <Windows.h> and <synchapi.h>.
cin >> text; will only read one word. To read the entire line you want getline(cin, text);.
It is easiest to first compute minutes per word stored in a floating point type. To get the total floating point minutes you can just divide the duration by 1.0min. This results in a long double. Then divide that total minutes by 12 to get the minutes per word:

.

auto mpw = (stop - start) / 1.0min / 12;

Then just invert mpw to get words per minute:

.

float wpm = 1/mpw;

In summary:

#include <chrono>
#include <iostream>
#include <thread>

using namespace std;
using namespace std::chrono;

int main()
{
    typedef steady_clock Time;
    typedef seconds s;

    string text;
    string ctext = "One two three four five six seven eight nine ten eleven twelve";

    cout << "Type: "<< ctext << " in" << "\n" << "5" << endl;
    this_thread::sleep_for(1s);
    cout << "4" << endl;
    this_thread::sleep_for(1s);
    cout << "3" << endl;
    this_thread::sleep_for(1s);
    cout << "2" << endl;
    this_thread::sleep_for(1s);
    cout << "1" << endl;
    this_thread::sleep_for(1s);
    cout << "GO" << endl;

    auto start = Time::now();
    getline(cin, text);
    auto stop = Time::now();

    auto mpw = (stop - start) / 1.0min / 12;
    float wpm = 1/mpw;

    if (ctext == text)
    {
        cout << "Correct! WPM: " << wpm << '\n';
    }
    else
    {
        cout << "You had some errors. Your WPM: " << wpm << '\n';
    }
}

How do I convert std::chrono to int

1 Answers1