#include<bits/stdc++.h>
using namespace std;
using Int = long long;
//INSERT ABOVE HERE
signed 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;
}