题解 | #牛牛学数列3#
牛牛学数列3
https://www.nowcoder.com/practice/f65c726d081c4160a9356eabf0dc21d9
#include <stdio.h>
int main() {
int a,i,count=1;
float sum=0;
scanf("%d",&a);
for(i=1;i<=a;i++)
{
sum+=1.0/(count*i);
count*=-1;
}
printf("%.3f\n",sum);
return 0;
}

