编辑代码

#include <stdio.h>
int main () {
    int n,i;
    float fn=1.0,one=-1.0;
    scanf("%d",&n);
    for(i=2.0;i<=n;i++){
      fn+=one/i;
      one=-one;
    }
    printf("f(%d)=%f",n,fn);
    return 0;
}