题解 | #求1+2+3+...+n#巧用static成员
求1+2+3+...+n
https://www.nowcoder.com/practice/7a0da8fc483247ff8800059e12d7caf1
class Sum
{
public:
Sum()
{
_ret+=_i;
++_i;
}
static int GetRet()
{
return _ret;
}
private:
static int _i;
static int _ret;
};
int Sum :: _i=1;
int Sum :: _ret=0;
class Solution {
public:
int Sum_Solution(int n) {
Sum a[n];
return Sum::GetRet();
}
};
