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How should I find the execution time of a program in c++?

+2 votes
asked Mar 13, 2023 by Nirali Patel (750 points)

2 Answers

+1 vote
answered Mar 13, 2023 by Fatima Suleiman Atta (320 points)
The function clock() returns the number of clock ticks since the program started executing. If you divide it by the constant CLOCKS_PER_SEC you will get how long the program has been running, in seconds.
0 votes
answered Mar 13, 2023 by Peter Minarik (88,520 points)
edited Mar 15, 2023 by Peter Minarik
C++ way:

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

int main()
{
    using clock = std::chrono::steady_clock;
    clock::time_point start = clock::now();
    std::this_thread::sleep_for(std::chrono::seconds(5));
    clock::time_point end = clock::now();
    clock::duration execution_time = end - start;
    std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(execution_time).count() << std::endl;
}
commented Mar 13, 2023 by Nirali Patel (750 points)
I tried using that way as you advised, but I am getting errors. I don't know how to fix. I have never done execution time in my code. can you please help me? Thank you.
Here is the code:
https://onlinegdb.com/kkX2X1Lb9
commented Mar 13, 2023 by xDELLx (10,520 points)
#include <chrono>

Add this
commented Mar 13, 2023 by Nirali Patel (750 points)
okay, I added that library, but still I don't get the execution time of my program
commented Mar 15, 2023 by Peter Minarik (88,520 points)
I've updated my original answer to include printing the duration converted to milliseconds. I hope this helps.
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