#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <ctime>
#include <cstring>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <numeric>
#include <utility>
#include <iomanip>
#include <algorithm>
#include <functional>
using namespace std;

typedef long long ll;
typedef vector<int> vint;
typedef vector<long long> vll;
typedef pair<int,int> pint;
typedef pair<long long, long long> pll;

#define MP make_pair
#define PB push_back
#define ALL(s) (s).begin(),(s).end()
#define EACH(i, s) for (__typeof__((s).begin()) i = (s).begin(); i != (s).end(); ++i)
#define COUT(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << endl

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<class T1, class T2> ostream& operator << (ostream &s, pair<T1,T2> P) 
{ return s << '<' << P.first << ", " << P.second << '>'; }
template<class T> ostream& operator << (ostream &s, vector<T> P) 
{ for (int i = 0; i < P.size(); ++i) { if (i > 0) { s << " "; } s << P[i]; } return s; }
template<class T1, class T2> ostream& operator << (ostream &s, map<T1,T2> P) 
{ EACH(it, P) { s << "<" << it->first << "->" << it->second << "> "; } return s; }



typedef long double DD;

const DD INF = 1LL<<61;
const DD EPS = 1e-10;
const DD PI = acos(-1.0);
DD torad(int deg) {return (DD)(deg) * PI / 180;}
DD todeg(DD ang) {return ang * 180 / PI;}

struct Point {
    DD x, y;
    Point(DD x = 0.0, DD y = 0.0) : x(x), y(y) {}
    friend ostream& operator << (ostream &s, const Point &p) {return s << '(' << p.x << ", " << p.y << ')';}
};

Point operator + (const Point &p, const Point &q) {return Point(p.x + q.x, p.y + q.y);}
Point operator - (const Point &p, const Point &q) {return Point(p.x - q.x, p.y - q.y);}
Point operator * (const Point &p, DD a) {return Point(p.x * a, p.y * a);}
Point operator * (DD a, const Point &p) {return Point(a * p.x, a * p.y);}
Point operator * (const Point &p, const Point &q) {return Point(p.x * q.x - p.y * q.y, p.x * q.y + p.y * q.x);}
Point operator / (const Point &p, DD a) {return Point(p.x / a, p.y / a);}
Point conj(const Point &p) {return Point(p.x, -p.y);}
Point rot(const Point &p, DD ang) {return Point(cos(ang) * p.x - sin(ang) * p.y, sin(ang) * p.x + cos(ang) * p.y);}
Point rot90(const Point &p) {return Point(-p.y, p.x);}
DD cross(const Point &p, const Point &q) {return p.x * q.y - p.y * q.x;}
DD dot(const Point &p, const Point &q) {return p.x * q.x + p.y * q.y;}
DD norm(const Point &p) {return dot(p, p);}
DD abs(const Point &p) {return sqrt(dot(p, p));}
DD amp(const Point &p) {DD res = atan2(p.y, p.x); if (res < 0) res += PI*2; return res;}
bool eq(const Point &p, const Point &q) {return abs(p - q) < EPS;}
bool operator < (const Point &p, const Point &q) {return (abs(p.x - q.x) > EPS ? p.x < q.x : p.y < q.y);}
bool operator > (const Point &p, const Point &q) {return (abs(p.x - q.x) > EPS ? p.x > q.x : p.y > q.y);}
Point operator / (const Point &p, const Point &q) {return p * conj(q) / norm(q);}

bool compare_y(Point a, Point b) { return a.y < b.y; }

DD Rec(vector<Point>::iterator it, int n) {
    if (n <= 1) return INF;
    int m = n/2;
    double x = it[m].x;
    double d = min(Rec(it, m), Rec(it+m, n-m));
    inplace_merge(it, it+m, it+n, compare_y);
    
    vector<Point> vec;
    for (int i = 0; i < n; ++i) {
        if (fabs(it[i].x - x) >= d) continue;
        for (int j = 0; j < vec.size(); ++j) {
            double dx = it[i].x - vec[vec.size()-j-1].x;
            double dy = it[i].y - vec[vec.size()-j-1].y;
            if (dy >= d) break;
            d = min(d, sqrt(dx*dx+dy*dy));
        }
        vec.push_back(it[i]);
    }
    return d;
}

DD Closet(vector<Point> vp) {
    int n = vp.size();
    sort(vp.begin(), vp.end());
    return Rec(vp.begin(), n);
}



int n;
DD x, y;

int main() {
    while (cin >> n) {
        vector<Point> vp(n);
        for (int i = 0; i < n; ++i) {
            cin >> x >> y;
            vp[i] = Point(x, y);
        }
        double res = Closet(vp);
        cout << (ll)(res*res + EPS) << endl;
    }
    return 0;
}


Measured memory_bytes: 55664