#include <bits/stdc++.h>
using namespace std;
const long long OO = 1e9;
const long long mod = 1e9 + 7;
const double EPS = (1e-7);
int dcmp(double x, double y) { return fabs(x - y) <= EPS ? 0 : x < y ? -1 : 1; }
void fast() {
  std::ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
}
int x;
int main() {
  fast();
  while (cin >> x) {
    if (x == 1)
      cout << 1 << endl;
    else if (x == 3)
      cout << 5 << endl;
    if (x == 1 || x == 3) continue;
    for (int i = 3;; i += 2) {
      if ((i * i + 1) / 2 >= x) {
        cout << i << endl;
        break;
      }
    }
  }
  return 0;
}
