#include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < int(n); i++)
#define rrep(i, n) for (int i = int(n) - 1; i >= 0; i--)
#define reps(i, n) for (int i = 1; i <= int(n); i++)
#define rreps(i, n) for (int i = int(n); i >= 1; i--)
#define repi(i, a, b) for (int i = int(a); i < int(b); i++)
#define each(x, y) for (auto &x : y)
#define all(a) (a).begin(), (a).end()
#define bit(b) (1ll << (b))
#define uniq(v) (v).erase(unique(all(v)), (v).end())
#define rsort(v) sort(all(v)); reverse(all(v))

using namespace std;

using i32 = int;
using i64 = long long;
using f80 = long double;
using vi32 = vector<i32>;
using vi64 = vector<i64>;
using vf80 = vector<f80>;
using vstr = vector<string>;

inline void yes() { cout << "Yes" << '\n'; exit(0); }
inline void no() { cout << "No" << '\n'; exit(0); }
inline i64 gcd(i64 a, i64 b) { if (min(a, b) == 0) return max(a, b); if (a % b == 0) return b; return gcd(b, a % b); }
inline i64 lcm(i64 a, i64 b) { return a / gcd(a, b) * b; }
void solve(); int main() { ios::sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(16); solve(); return 0; }
template<typename T> class pqasc : public priority_queue<T, vector<T>, greater<T>> {};
template<typename T> class pqdesc : public priority_queue<T, vector<T>, less<T>> {};
template<typename T> inline void amax(T &x, T y) { if (x < y) x = y; }
template<typename T> inline void amin(T &x, T y) { if (x > y) x = y; }
template<typename T> inline T power(T x, i64 n) { T r = 1; while (n > 0) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; }
template<typename T> istream& operator>>(istream &is, vector<T> &v) { for (auto &x : v) is >> x; return is; }
template<typename T> ostream& operator<<(ostream &os, const vector<T> &v) { rep(i, v.size()) { if (i) os << ' '; os << v[i]; } return os; }

void solve() {
  int N; cin >> N;
  vector<pair<f80, f80>> xy;
  rep(i, N) {
    f80 x, y; cin >> x >> y;
    xy.push_back({x, y});
  }
  f80 ok = 1e18, ng = -1;
  while ((ok - ng) >= 1e-9) {
    f80 md = (ok + ng) / 2;
    int now = 0;
    vector<bool> visited(N);
    queue<pair<f80, f80>> q;
    visited[0] = true;
    q.push(xy[0]);
    while (!q.empty()) {
      f80 ax, ay;
      tie(ax, ay) = q.front(), q.pop();
      rep(i, N) {
        if (i == now) continue;
        if (visited[i]) continue;
        f80 bx = xy[i].first, by = xy[i].second;
        if (sqrt(pow(ax - bx, 2) + pow(ay - by, 2)) <= md) {
          visited[i] = true;
          q.push(xy[i]);
        }
      }
      if (visited[N - 1]) break;
    }
    if (visited[N - 1]) ok = md; else ng = md;
  }
  i64 ans = ((i64) ceil(ng) + 9) / 10 * 10;
  cout << ans << '\n';
}