#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

long long gcd(long long a, long long b){
	if(b==0) return a;
	return gcd(b, a%b);
}

long long lcm(long long a, long long b){
	if(a<b) swap(a,b);
	if(b==1) return a;
	return a * (b/gcd(a,b));
}


int main(){
	int n;
	cin >> n;
	vector<int> z(n);
	for(int i=0; i<n; i++){
		cin >> z[i];
	}

	cout << z.back() << "/" << z.front() << endl;
	return 0;
}