How to implement countdown Timers in c++? [duplicate] - c++

This question already has answers here:
How to use a timer in C++ to force input within a given time?
(5 answers)
Closed 6 years ago.
I'm writing a code where the user has to answer the question in 10 seconds or else he will lose, I know that I'm supposed to use threads but the problem is, I don't know how to do the timer, any ideas?
Thanks

You don't need threads.
Assuming time is in ms:
updateLoop(){
timeLeft = startingTime + 10.000 - now;
if (timeLeft <= 0) {
lose=true;
}
render();
}
EDIT: I probably misunderstood the question a bit. This seems to cover your question, as in #Mourad's comment:
How to use a timer in C++ to force input within a given time?

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Closed 11 years ago.
Possible Duplicate:
Sleep Less Than One Millisecond
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