#include <bits/stdc++.h>
int ans[10];
int main() {
  ans[1] = 1;
  ans[2] = 3;
  ans[3] = 5;
  ans[4] = 3;
  ans[5] = 3;
  int x;
  scanf("%d", &x);
  if (x < 6) {
    printf("%d\n", ans[x]);
    return 0;
  }
  for (int n = 0;; ++n) {
    int cnt;
    if (n % 2 == 0) {
      if (x % 4 != 0) continue;
      int m = n / 2 - 1;
      if (m % 2 == 0)
        cnt = m * m / 2;
      else
        cnt = (m * m) / 2 + 1;
      cnt *= 4;
      if (cnt >= x) {
        printf("%d\n", n);
        return 0;
      }
    } else {
      cnt = (n * n) / 2 + 1;
      if (cnt >= x) {
        printf("%d\n", n);
        return 0;
      }
    }
  }
  return 0;
}
