#include<iostream>
using namespace std;
const int maxn=1e7+1;
struct stu{
	int Numerator,denominator;
}enumeration[maxn];
int n;
int main(){
	cin>>n;
	long long ii=1;
	if(n==1){
		cout<<"1/1"<<endl;
		return 0;
	}
	for(long long i=2;ii<=n;i++){
		for(long long j=1;j<i;j++,ii++){
			enumeration[ii].Numerator=j;
			enumeration[ii].denominator=i-j;
//			cout<<enumeration[ii].Numerator<<"/"<<enumeration[ii].denominator<<endl;
//			cout<<ii<<endl;
		}
//		cout<<ii<<endl;
	}
	cout<<enumeration[n].Numerator<<"/"<<enumeration[n].denominator<<endl;
	return 0;
}

#2AC