47 lines
1.1 KiB
C++
47 lines
1.1 KiB
C++
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#include <iostream>
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#include <climits>
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//original function:
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long f(int n)
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{
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if(n == 0) return 0;
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else if(n < 0) return -f(-n);
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else return f(n-1) + 3*n*(n-1);
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}
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//My implementation:
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long f2(int n)
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{
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long result = 0;
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if(n<0)
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{
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for (long i = 0; i<=n*-1; i++)
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{
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result += -(3*i*i-3*i);
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}
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}
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else
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{
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for (long i = 0; i<=n; i++)
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{
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result += 3*i*i-3*i;
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}
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}
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return result;
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}
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int main()
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{
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//brute force check 😅:
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for (int i = -20000; i != INT_MAX ; i++){
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if(f(i) != f2(i))
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{
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std::cout << i << " WRONG!!😦 " << f(i) << " != "<< f2(i) << "\n";
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/* Its seems like my implementation works well, until it reches the number 26756, there it
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outputs 19154179862460 instead of 19149884895164 and the error only gets worse from there.
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I have no idea why this happens, and i dont have time to figure it out 🙃
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Please enlighten me if you can!
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*/
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break;
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}
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}
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}
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