面接問題46 1+2+3+...+n

class Temp{



public:

    Temp(){

        ++N;

        sum+=N;

    }

    static void Reset(){

        N = 0;

        sum = 0;

    }

    static int getSum(){

        return sum;

    }



private:

    static int N;

    static int sum;

};

int Temp::N = 0;

int Temp::sum = 0;





int sum(int n){



    Temp::reset();

    Temp * a = new Temp[n];

    delete []a;

    return Temp::getSum();

    

}