/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author
 */

#include <iostream>
#include <fstream>

#ifndef SOLUTION_COMMON_H

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using PI = pair<int, int>;
template<class T> using V = vector<T>;
using VI = V<int>;
#define _1 first
#define _2 second

#ifdef MY_DEBUG
# define DEBUG(x) x
#else
# define DEBUG(x)
#endif

template<class T>
inline void debug(T &A) {
  DEBUG(
      for (const auto &a : A) {
        cerr << a << " ";
      }
      cerr << '\n';
  )
}

template<class T, class Func>
inline void debug_with_format(T &A, Func f) {
  DEBUG(
      for (const auto &a : A) {
        cerr << f(a) << " ";
      }
      cerr << '\n';
  )
}

template<class T>
inline void debug_dim2(T &A) {
  DEBUG(
      for (const auto &as : A) {
        debug(as);
      }
  )
}

template<typename ... Args>
inline void debug(const char *format, Args const &... args) {
  DEBUG(
      fprintf(stderr, format, args ...);
      cerr << '\n';
  )
}

template<typename ... Args>
string format(const string &fmt, Args ... args) {
  size_t len = snprintf(nullptr, 0, fmt.c_str(), args ...);
  vector<char> buf(len + 1);
  snprintf(&buf[0], len + 1, fmt.c_str(), args ...);
  return string(&buf[0], &buf[0] + len);
}

template<class T1, class T2>
string fmtP(pair<T1, T2> a) {
  stringstream ss;
  ss << "(" << a._1 << "," << a._2 << ")";
  return ss.str();
}

#define SOLUTION_COMMON_H

#endif //SOLUTION_COMMON_H

const int MOD = 1000000007;

class A {
public:
  void solve(std::istream& in, std::ostream& out) {
    int N;
    in >> N;
    string s;
    getline(in, s); // 改行を消す
    getline(in, s);

    int cnt = 0;
    for (char i : s) {
      if (isdigit(i)) cnt++;
    }
    if (cnt != s.size()) {
      out << "\"assert\"";
    } else {
      V<ll> A(3);
      A[0] = stoll(s);
      in >> A[1] >> A[2];

      ll a = A[0] + A[1];
      ll b = A[0] + A[2];
      ll c = A[1] + A[2];
      debug("%d %d %d", a, b, c);
      set<ll> B = {a, b, c};
      debug(B);
      out << *(--(--B.end()));
    }
  }
};


int main() {
	A solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
	return 0;
}