text: #include <cstdio>
  #include <iostream>
  #include <vector>
  #include <algorithm>
  
  using namespace std;
  
  #define DOLLAR_TO_MARK 1
  #define MARK_TO_DOLLAR 2
  
  struct Conversation {
      int Value = 0;
      int Date = 0;
      int ShouldBe = 0;
  
      float ToMark(float dollar) const { return dollar * Value; }
      float ToDollar(float mark) const { return mark / Value; }
  };  // struct Conversation
  
  int main(/*int argc, char *argv[]*/) {
      // ios::sync_with_stdio(false);
  
      int n;
      cin >> n;
  
      vector<Conversation> con(n);
      int cnt = 1;
      for (auto &e : con) {
          cin >> e.Value;
          e.Date = cnt++;
      }  // foreach in con
  
      vector<Conversation *> tmp(n);
      for (int i = 0; i < tmp.size(); i++) { tmp[i] = &con[i]; }  // for
  
      std::sort(tmp.begin(), tmp.end(),
                [](const Conversation *a, const Conversation *b) {
                    return a->Value < b->Value;
                });
  
      int bound = n / 2;
      for (int i = 0; i < bound; i++) {
          tmp[i]->ShouldBe = MARK_TO_DOLLAR;
          tmp[tmp.size() - i - 1]->ShouldBe = DOLLAR_TO_MARK;
      }  // for
  
      float money = 100.0f;
      for (int i = 0; i < con.size(); i++) {
          if (con[i].ShouldBe == DOLLAR_TO_MARK) {
              float m = money;
              m = con[i].ToMark(money);
  
              int next = -1;
              int min = INT_MAX;
              for (int j = i + 1;
                   con[j].ShouldBe != DOLLAR_TO_MARK && j < con.size();
                   j++) {
                  if (con[j].ShouldBe == MARK_TO_DOLLAR && con[i].Value < min) {
                      min = con[i].Value;
                      next = j;
                  }
              }  // for
  
              if (next != -1) {
                  money = con[next].ToDollar(m);
              } else if (i == con.size() - 2 && con[i + 1].ShouldBe == 0) {
                  money = con[i + 1].ToDollar(m);
              }
          }
      }  // for
  
      printf("%.2f\n", money);
  
      return 0;
  }  // function main
  