Thread: How to add times elapsed from function inside a loop?

  1. #1
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    How to add times elapsed from function inside a loop?

    I have implemented two ways of doing something inside a loop. I'd like to time them to find out which to keep.

    Code:
    for(int i = 0; i < 1000; i++)
    {
        int x = whatever(i);
        foo1(x);
        foo2(x)
    }
    How can I find out the total time of foo1 and foo2? I tried declaring an std::chrono variable outside the for loop and measuring foo1 and food2 with now() but times elapsed can't be added.

  2. #2
    and the hat of int overfl Salem's Avatar
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    You would need to do
    Code:
    t1 = std::chrono::high_resolution_clock::now();
    for(int i = 0; i < 1000; i++)
    {
        int x = whatever(i);
        foo1(x);
    }
    t2 = std::chrono::high_resolution_clock::now();
    for(int i = 0; i < 1000; i++)
    {
        int x = whatever(i);
        foo2(x);
    }
    t3 = std::chrono::high_resolution_clock::now();
    Then foo1 takes t2-t1 and foo2 takes t3-t2.
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