/*找规律啊*/

#include<iostream>

#include<cstdio>

#include<algorithm>

using namespace std;

int sum[],n;

int main(){

    for(int i=;i<=;i++)sum[i]=sum[i-]+i;

    scanf("%d",&n);

    int pos=lower_bound(sum+,sum+,n)-sum;

    int s=sum[pos-]+;int plus=pos+;//分子和分母之和为plus

    int mu=n-s+;

    int z=plus-mu;

    if(pos%==)swap(z,mu);

    printf("%d/%d",z,mu);

}