#include <bits/stdc++.h>
using namespace std;
typedef long double ld;
const long long INF = 2e18;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  long long x, i, s = 4;
  cin >> x;
  long long dp[100000] = {0};
  if (x == 3) {
    cout << "5";
    return 0;
  }
  for (i = 0; i < 100000; i++) {
    dp[i] = INF;
  }
  dp[1] = 1;
  for (i = 3; i < 100000; i += 2) {
    dp[i] = dp[i - 2] + s;
    s += 4;
  }
  for (i = 1; i < 20; i += 2) {
    if (dp[i] >= x) {
      cout << i;
      return 0;
    }
  }
  return 0;
}
