#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main(){
  string n;getline(cin,n);
  string s;
  getline(cin,s);
  for(int i = 0; s.size()-1 > i; i++){
    if(!('0' <= s[i] && s[i] <= '9')){
      cout << "\"assert\"" << endl;
      return 0;
    }
  }
  vector<long long> A(3);
  A[0] = stol(s);
  cin>>A[1]>>A[2];
  vector<long long> B;
  for(int i = 0; 3 > i; i++){
    for(int j = 0; 3 > j; j++){
      if(i==j)continue;
      B.push_back(A[i]+A[j]);
    }
  }
  sort(B.begin(),B.end());
  B.erase(unique(B.begin(),B.end()),B.end());
  cout << B[B.size()-2] << endl;
}