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 (GCC 5.4.1) (judge verdict: Runtime Error)

#include "stdio.h"
#include "stdlib.h"
#include "stdbool.h"

int main(int argc,char *argv[]){
    float i;
    float result;
    float num = atof(argv[1]);
    bool flag = false;


    if (( (int)num & 1 ) == 1){
        flag = true;
    }

    i = num / 2 ;
    
    if(flag == true){
        i = i + 1;
    }
    result = i / num;

  printf("%f¥n",result);
   
}