#include <bits/stdc++.h>
using namespace std;
int a[1001][1001];
bool can(int x, int n) {
  int kek = 1;
  if (n & 1) {
    if (x % 2 == 0) return false;
    a[x / 2 + 1][x / 2 + 1] = 1;
    --n;
    kek = 0;
  }
  for (int i = 1; i <= x; i++)
    for (int j = 1; j <= x; j++) a[i][j] = 0;
  for (int i = 1; i <= x / 2 - (x % 2 == 0); i++)
    for (int j = 1; j <= x / 2 - (x % 2 == 0); j++)
      if (n >= 4 && !a[i - 1][j] && !a[i][j - 1]) {
        n -= 4;
        a[i][j] = 1;
      }
  if (x & 1) {
    for (int i = 1; i < x / 2 + kek; i++)
      if (!a[x / 2][i] && !a[x / 2 + 1][i - 1] && n >= 2) {
        n -= 2;
        a[x / 2 + 1][i] = 1;
      }
    for (int i = 1; i < x / 2 + kek; i++)
      if (!a[i][x / 2] && !a[i - 1][x / 2 + 1] && n >= 2) {
        n -= 2;
        a[i][x / 2 + 1] = 1;
      }
  }
  return n == 0;
}
int main() {
  int n;
  cin >> n;
  if (n == 1) {
    cout << 1 << "\n";
    return 0;
  }
  for (int i = 3; i <= 1000; i++)
    if (can(i, n)) {
      cout << i << "\n";
      return 0;
    }
}
