题解 | #牛牛学数列#
牛牛学数列
https://www.nowcoder.com/practice/0b97367cd2184c12a0e02f7c223aee11
#include <stdio.h>
#include <math.h>
int main() {
int n;
int sum=0;
scanf("%d",&n);
for(int i=1;i<=n;i++)
{
sum+=(i*pow(-1,i+1));
}
printf("%d\n",sum);
}
