#include using namespace std; #define FOR(i,a,b) for(int i=(a);i<(b);i++) #define REP(i,n) FOR(i,0,n) #define ALL(v) (v).begin(),(v).end() template inline bool chmax(A &a, B b) { if (a inline bool chmin(A &a, B b) { if (a>b) { a=b; return 1; } return 0; } typedef unsigned long long ull; typedef long long ll; typedef pair pii; typedef pair pll; typedef pair P; const ll INF = 1ll<<29; const ll MOD = 1000000007; const double EPS = 1e-10; struct UnionFind { vector par; vector rank; UnionFind() {} UnionFind(int n) { init(n); } int operator[] (int x) { return find(x); } void init(int n) { par.resize(n); rank.resize(n); REP(i, n) { par[i] = i; rank[i] = 0; } } int find(int x) { if (par[x] == x) return x; return par[x] = find(par[x]); } void unite(int x, int y) { x = find(x); y = find(y); if (x == y) return; if (rank[x] < rank[y]) { par[x] = y; } else { par[y] = x; if (rank[x] == rank[y]) rank[x]++; } } bool same(int x, int y) { return find(x) == find(y); } }; int n; ll x[1000], y[1000], d[1000][1000]; int main() { cin >> n; REP(i, n) scanf("%lld %lld", x + i, y + i); REP(i, n) FOR(j, i + 1, n) d[i][j] = (x[i]-x[j])*(x[i]-x[j]) + (y[i]-y[j])*(y[i]-y[j]); ll l = 0, r = INF; while (r - l > 1) { ll m = (r + l) / 2; ll x = (m * 10) * (m * 10); UnionFind uf(n); REP(i, n) FOR(j, i + 1, n) if (d[i][j] <= x) uf.unite(i, j); if (uf[0] == uf[n - 1]) r = m; else l = m; } printf("%lld\n", r * 10); return 0; }