#include <string>
#include <vector>
 
using namespace std;
 
int solution(int left, int right)
{
    int answer = 0;
 
    for (int i = left; i <= right; ++i)
    {
        int iAnswer = 0;
 
        for (int j = 1; j <= i; ++j)
        {
            if (i % j == 0)
                ++iAnswer;
        }
 
        if (iAnswer % 2 == 0)
            answer += i;
        else
            answer -= i;
 
        iAnswer = 0;
    }
 
    return answer;
}

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