#include <cstdio>
#include <cstring>
#include <algorithm>

int N;
long long X[1001], Y[1001];
bool used[1001];

long long dist(int i, int j){
    long long dx = std::abs(X[i] - X[j]),
        dy = std::abs(Y[i] - Y[j]);
    return dx * dx + dy * dy;
}

bool dfs(int u, long long limit){
    used[u] = true;
    if(u == N){return true;}

    bool res = false;
    for(int i=1;i<=N;i++){
        if(used[i]){continue;}
        if(dist(u, i) <= limit * limit){res |= dfs(i, limit);}
    }

    return res;
}

int main(){
    scanf("%d", &N);

    for(int i=1;i<=N;i++){
        scanf("%lld %lld", X+i, Y+i);
    }

    long long lb = 0ll, ub = 252521000ll;
    while(ub - lb > 1){
        long long mid = (lb + ub) / 2 * 10;
        memset(used, 0, sizeof(used));
        if(dfs(1, mid)){
            ub = mid / 10;
        }else{
            lb = mid / 10;
        }
    }

    printf("%lld\n", ub * 10);
}