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,i,sum=0;;
scanf("%d",&n);
for(i=1;i<=n;i++)
{
sum+=i*pow(-1,i-1);
}
printf("%d",sum);
return 0;
}
