#include using namespace std; #define rep(i,n) for(ll i=0;i=0;i--) #define perl(i,r,l) for(ll i=r-1;i>=l;i--) #define fi first #define se second #define pb push_back #define ins insert #define pqueue(x) priority_queue,greater> #define all(x) (x).begin(),(x).end() #define CST(x) cout<; using vvl=vector>; using pl=pair; using vpl=vector; using vvpl=vector; const ll MOD=1000000007; const ll MOD9=998244353; const int inf=1e9+10; const ll INF=4e18; const ll dy[8]={1,-1,0,0,1,1,-1,-1}; const ll dx[8]={0,0,1,-1,1,-1,1,-1}; template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } struct UnionFind { vector par; UnionFind(int n) : par(n, -1) {} int root(int x) { if (par[x] < 0) return x; else return par[x] = root(par[x]); } bool same(int x, int y) { return root(x) == root(y); } bool merge(int x, int y) { x = root(x); y = root(y); if (x == y) return false; if (par[x] > par[y]) swap(x, y); par[x] += par[y]; par[y] = x; return true; } int size(int x) { return -par[root(x)]; } }; int main(){ ll n;cin >> n; vl x(n),y(n); rep(i,n)cin >> x[i] >> y[i]; ll ng=0;ll ok=inf*2/10; while(ok-ng>1){ ll mid=(ok+ng)/2; ll len=mid*10; UnionFind uf(n); rep(i,n){ repl(j,i+1,n){ if(len*len>=(x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j]))uf.merge(i,j); } } if(uf.same(0,n-1))ok=mid; else ng=mid; } cout << ok*10 <