#include <bits/stdc++.h>
using namespace std;
const int maxn = 100 + 5;
const int INF = 100000;
const int Mod = 1000000000 + 9;
int f[maxn];
int main() {
  f[1] = f[2] = 1;
  for (int i = 3; i < maxn; i += 2) {
    f[i] = f[i + 1] = (i / 2) * i + (i / 2 + 1);
  }
  int n;
  while (cin >> n) {
    if (n == 3) {
      cout << 5 << endl;
      continue;
    }
    for (int i = 1; i < maxn; i += 2) {
      if (n <= f[i]) {
        cout << i << endl;
        break;
      }
    }
  }
  return 0;
}
