面试题 46 1+ 2＋3+...+n

class Temp{

public:
    Temp(){
        ++N;
        sum+=N;
    }
    static void Reset(){
        N = ;
        sum = ;
    }
    static int getSum(){
        return sum;
    }

private:
    static int N;
    static int sum;
};
int Temp::N = ;
int Temp::sum = ;

int sum(int n){

    Temp::reset();
    Temp * a = new Temp[n];
    delete []a;
    return Temp::getSum();

}