what's wrong in my code:
#include <iostream>
int main()
{
    int N;
    std::cin >> N;
    int result=0;
    if (N=0){
        std::cout << 1 << std::endl;
        return 0;
    }
    if (N > 0)
    {
        for (int i=2; i<=N;i++)
        {
            result+=i;
        }
        std::cout << result << std::endl;
        return 0;
    }else
    {
        for (int i=-2;i >=N;i--)
        {
            result+=i;
        }
        std::cout << result << std::endl;
        return 0;
    }
    return 0;
}

Edited by author 18.10.2013 23:00