题解 | #求1+2+3+...+n#
求1+2+3+...+n
https://www.nowcoder.com/practice/7a0da8fc483247ff8800059e12d7caf1
class A{ public: A(){ ++N; sum+=N; } static void Reset(){ N=0; sum=0; } static int N; static int sum; }; int A::N=0; int A::sum=0; class Solution { public: int Sum_Solution(int n) { A::Reset(); A *a=new A[n]; delete []a; a=nullptr; return A::sum; } };