#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <string>

using namespace std;

int main() {
	int n;
	cin >> n;

	vector<int> a(n, 0);
	for (int i = 0; i < n; i++) {
		cin >> a[i];
	}
	cout << a[n - 1] << "/" << a[0] << endl;
	return 0;
}