Problem:
Score : 100 points

Problem Statement

Given is an integer N.

Takahashi chooses an integer a from the positive integers not greater than N with equal probability.

Find the probability that a is odd.

Constraints

1 \leq N \leq 100

Input

Input is given from Standard Input in the following format:

N

Output

Print the probability that a is odd.
Your output will be considered correct when its absolute or relative error from the judge's output is at most 10^{-6}.

Sample Input 1

4

Sample Output 1

0.5000000000

There are four positive integers not greater than 4: 1, 2, 3, and 4. Among them, we have two odd numbers: 1 and 3. Thus, the answer is \frac{2}{4} = 0.5.

Sample Input 2

5

Sample Output 2

0.6000000000

Sample Input 3

1

Sample Output 3

1.0000000000

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;
using System.Collections.Generic;

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            MainStream();
        }
        static void MainStream()
        {
            Scan sc = new Scan();
            write wr = new write();

            int n = sc.intarr[0];

            int child = n - (n / 2);
            float ans = (float)child / n;

            wr.wri(ans);


        }


    }

    class Scan
    {
        public string str => Console.ReadLine();

        public string[] strarr => str.Split(' ');

        public long[] longarr => strarr.Select(long.Parse).ToArray();
        public int[] intarr => strarr.Select(int.Parse).ToArray();
        public char[] chararr => str.ToArray();


    }



    class write
    {
        public void wri<Type>(Type x)
        {
            Console.WriteLine(x);
        }
    }

    class Method
    {
        static public int max(params int[] nums)
        {

            int maxx = nums[0];
            for (int i = 1; i < nums.Length; i++)
            {
                maxx = Math.Max(maxx, nums[i]);
            }
            return maxx;
        }
    }
}