#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<cstdlib>
#include<algorithm>
#include<bitset>
#include<vector>
#include<list>
#include<deque>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<cmath>
#include<sstream>
#include<fstream>
#include<iomanip>
#include<ctime>
#include<complex>
#include<functional>
#include<climits>
#include<cassert>
#include<iterator>
#include<unordered_map>
#include<unordered_set>
//#include<quadmath.h>
using namespace std;

int main(){
	int n;
	scanf("%d", &n);
	vector<long long int> v;
	for (int i = 0; i < n; i++){
		long long int a;
		scanf("%lld", &a);
		v.push_back(a);
	}
	long long int k = __gcd(v[0], v.back());
	v[0] /= k;
	v.back() /= k;
	printf("%lld/%lld\n", v.back(), v[0]);
	return 0;
}