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: Wrong Answer)

#include <stdio.h>
#include<string.h>
#include<stdlib.h>
#include<math.h>
long long cmpfunc (const void * a, const void * b) {
   return ( *(long long*)a - *(long long*)b );
}



int main(void){
   
long long int test,i,j,n,count,flag=0,o1=0,o2=0,b1,x,m,l,max,sum2,min,f,c,r,o,sum1,sum=0,y,a,b,count1=0,a2,b2;

scanf("%lld",&n);
if(n==1){
    printf("1.0000000000");
}else{
    if(n%2==0){
        printf("0.5000000000");
    }else{
         printf("0.6000000000");
    }
}
return 0;
}