#include <bits/stdc++.h>
const double E = 1e-8;
const double PI = acos(-1);
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  int x;
  cin >> x;
  int ans = 15;
  if (x <= 1)
    ans = 1;
  else if (x == 3)
    ans = 5;
  else if (x <= 5)
    ans = 3;
  else if (x <= 13)
    ans = 5;
  else if (x <= 25)
    ans = 7;
  else if (x <= 41)
    ans = 9;
  else if (x <= 61)
    ans = 11;
  else if (x <= 85)
    ans = 13;
  cout << ans << endl;
}
