题解 - 苏州市吴江区中学生信息编程竞赛域

12209水宇辰 (12209水宇辰) LV 9 @ 2022-01-27 10:01:53

#include<iostream>
#include<iomanip>
using namespace std;
int main( ) 
{
    long long n;
    long double sum=0;
    cin>>n;
    for(long double i=1;i<=2*n-1;i+=2)
    {
        sum+=1/i;
    }
    cout<<fixed<<setprecision(6)<<sum;
    return 0;
}

1
12227顾开 (12227顾开) LV 8 @ 2022-01-17 09:29:08

#include<iostream>
#include<iomanip>
using namespace std;
int main( )
{
long long n;
long double sum=0;
cin>>n;
for(long double i=1;i<=2*n-1;i+=2)
{
sum+=1/i;
}
cout<<fixed<<setprecision(6)<<sum;
return 0;
}
0
12203沈宇阳 (12203沈宇阳) LV 8 @ 2022-06-20 09:33:08

#include<iostream>
#include<iomanip>
using namespace std;
int main( )
{
long long n;
long double sum=0;
cin>>n;
for(long double i=1;i<=2*n-1;i+=2)
{
sum+=1/i;
}
cout<<fixed<<setprecision(6)<<sum;
return 0;
}