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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;
 
public class Main {
  public static void main(String args[]) {
 
	//入力値取得
	Scanner in = new Scanner(System.in);
	int num = in.nextInt();
    
    int kisuu = 0;
    //入力値の数ループする
    for (int i = 1; i <= num;  i++){
      //奇数の場合はカウントする
      if (i % 2 != 0){
        kisuu++;
      }
    }
    
    //奇数の確率を出力する
    System.out.println((double)kisuu / num);
        
  }
}