#include <bits/stdc++.h>
using namespace std;
const int Mod = 1e9 + 7;
const int maxn = 100005;
const int inf = 0x3f3f3f3f;
int m, n;
int main() {
  while (scanf("%d", &n) != EOF) {
    if (n == 3) {
      cout << 5 << endl;
      continue;
    }
    if (n % 4 == 2 || n % 4 == 3) {
      n += 2;
    }
    int ans;
    ans = sqrt(n * 2 - 2) + 1;
    if (ans % 2 == 0) ans++;
    cout << ans << endl;
  }
  return 0;
}
