#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<ll, int> pli;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;

int main(){
    int N;
    cin >> N;
    vll X(N), Y(N);
    vi vis(N);
    rep(i, N){
        scanf("%lld%lld", &X[i], &Y[i]);
    }

    priority_queue<pli, vector<pli>, greater<pli>> Q;
    Q.push(mp(0, 0));
    while(sz(Q)){
        ll d, p;
        tie(d, p) = Q.top();
        Q.pop();
        if(p == N - 1){
            ll ans = (ll)sqrt(d);
            ans -= ans % 10;
            while(ans*ans < d)ans += 10;
            cout << ans << endl;
            return 0;
        }
        if(vis[p]++)continue;
        rep(i, N)if(!vis[i]){
            ll nd = max(d, (X[i] - X[p])*(X[i] - X[p]) + (Y[i] - Y[p])*(Y[i] - Y[p]));
            Q.push(mp(nd, i));
        }
    }
}