1. using std::cout << "\n" instead of std::cout << endl to prevent flushing output buffers. Source: this
2. using inline void triangle(int &num, int &interval) speed up 10% time
3. using n(n+1)/2 according to this

1. using std::cout << "\n" instead of std::cout << endl to prevent flushing output buffers. Source: this
2. using inline void triangle(int &num, int &interval) speed up 10% time
3. using n(n+1)/2 according to this

The code takes far too long to complete (over 10 minutes). Is there any way to optimize the run-time? And, to make it more elegant?

So I only need to iterate up to half of the limit. But how can I implement that into my code? to only iterate up to half as many factor. Thankyou

The code takes far too long to complete (over 10 minutes). Is there any way to optimize the run-time and to make it more elegant?

So I only need to iterate up to half of the limit. But how can I implement that into my code to only iterate up to half as many factor?