#include<bits/stdc++.h>
#define ll long long
using namespace std;

int main(){
    double s=0;
    ll n;
    cin >> n;
    for (ll i=1;i<=n;++i){
        s+=pow((-1),(i-1))/(i*i+1);
        //meothinhle
    }
    cout<<fixed<<setprecision(4)<<s<<"\n";
    double x=0;
    int z=1;
    while (x<=n){
        x+=(double)z/(z+1);
        z+=1;
    }
    cout<<z-2;
    return 0;
}

#include <bits/stdc++.h>
#define int long long
using namespace std;
signed main()
{
    int n;
    cin >> n;
    double s = 0.0;
    for (int i = 1; i <= n; i ++)
    {
        double c = 1.0 / (i * i + 1);
        if (i % 2 == 0) s -= c;
        else s += c;
    }
    double s1 = 0.0;
    int x = 0;
    while (true)
    {
        x++;
        s1 += (double)x / (x + 1);
        if (s1 > n)
        {
            x--;
            break;
        }
    }
    cout << fixed << setprecision(4) << "S: " << s << endl;
    cout << "x: " <<x;
}