#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ul = unsigned long;
using ull = unsigned long long;

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	ll n;
	cin >> n;

	vector<ll> z(n);

	for (auto&& it : z)
		cin >> it;

	cout << to_string(z.back()) + "/" + to_string(z.front()) << "\n";

	return 0;
}