#include <iostream>
#include <vector>
#include <deque>

using namespace std;

struct point{
    long long x, y;
    point(long long x = 0, long long y = 0) : x(x), y(y) {}
    point operator-() const { return point(-x, -y); }
    point operator+(point p) const { return point(x + p.x, y + p.y); }
    point operator-(point p) const { return (*this) + (-p); }
    long long len() const { return x*x + y*y; }
};

inline long long cross(point a, point b) { return a.x * b.y - b.x * a.y; }

inline int sgn(long long x) { return (x > 0) - (x < 0); }

inline int dir(point a, point b, point c) { return sgn(cross(b-a, c-a)); }

inline bool contains(point a, point b, point c, point d){
    int d1 = dir(a, b, d);
    int d2 = dir(b, c, d);
    int d3 = dir(c, a, d);
    return d1 == d2 && d2 == d3;
}

vector<vector<int>> g;
vector<bool> vis, done;
vector<point> v;

void add_edge(int x, int y){
    if(dir(v[x], v[y], point(0, 0)) > 0) g[x].push_back(y);
    else g[y].push_back(x);
}

bool dfs(int x){
    vis[x] = true;
    for(int y : g[x]){
        if((vis[y] && !done[y]) || (!vis[y] && dfs(y))) return true;
    }
    done[x] = true;
    return false;
}

const long long INF = 8e18 + 1;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin>>n;

    v.resize(n);
    for(auto &[x, y] : v) cin>>x>>y;

    long long lo = 0, hi = INF;
    while(lo + 1 < hi){
        long long mid = lo + (hi - lo) / 2;
        deque<pair<int, int>> q;
        vector<vector<bool>> used(n, vector<bool>(n));
        for(int i = 0; i < n; i++){
            for(int j = i+1; j < n; j++){
                if((v[i]-v[j]).len() <= mid){
                    q.emplace_back(i, j);
                    used[i][j] = used[j][i] = true;
                }
            }
        }
        g.assign(n, vector<int>());
        while (!q.empty()) {
            int x = q.front().first, y = q.front().second;
            q.pop_front();
            add_edge(x, y);
            for(int i = 0; i < n; i++){
                if(i == x || i == y || contains(v[x], v[y], v[i], point(0, 0))) continue;
                if(used[x][i] && !used[y][i]) {
                    q.emplace_back(y, i);
                    used[y][i] = used[i][y] = true;
                }
                if(!used[x][i] && used[y][i]) {
                    q.emplace_back(x, i);
                    used[x][i] = used[i][x] = true;
                }
            }
        }
        vis.assign(n, false);
        done.assign(n, false);
        bool ok = false;
        for(int i = 0; i < n; i++){
            if(!vis[i]){
                ok = ok || dfs(i);
            }
        }
        if(ok) hi = mid;
        else lo = mid;
    }

    if(hi == INF) cout<<-1<<'\n';
    else cout<<hi<<'\n';

    return 0;
}