import std.stdio, std.string, std.conv, std.range;
import std.algorithm, std.array, std.typecons, std.container;
import std.math, std.numeric, std.random, core.bitop;

enum inf = 1_001_001_001;
enum infl = 1_001_001_001_001_001_001L;
enum mod = 1_000_000_007L;

alias Point = Tuple!(double, "x", double, "y");

enum eps = 1e-11;

void main() {
    int N;
    scan(N);
    auto ps = new Point[](N);

    foreach (i ; 0 .. N) {
        double xi, yi;
        scan(xi, yi);
        ps[i] = Point(xi, yi);
    }

    double ng = 0, ok = 1000000;

    foreach (t ; 0 .. 100) {
        double mid = (ng + ok) / 2;
        Point[] cs;

        foreach (i ; 0 .. N) {
            foreach (j ; i + 1 .. N) {
                if (dist(ps[i], ps[j]) > 2*mid + eps) {
                    ng = mid;
                    continue;
                }
                cs ~= f(ps[i], ps[j], mid);
            }
        }

        debug {
            writeln(cs);
        }

        bool check;

        foreach (ci ; cs) {
            bool b = true;
            foreach (i ; 0 .. N) {
                if (dist(ci, ps[i]) > mid + eps) b = false;
            }
            if (b) check = true;
        }

        (check ? ok : ng) = mid;
    }

    writefln("%.12f", ok);
}


double dist(Point p, Point q) {
    return sqrt((p.x - q.x)^^2 + (p.y - q.y)^^2);
}

Point[] f(Point p, Point q, double R) {
    auto xm = (p.x + q.x) / 2;
    auto ym = (p.y + q.y) / 2;
    auto h = sqrt(R^^2 - (p.x - xm)^^2 - (p.y - ym)^^2);
    auto v = [q.x - p.x, q.y - p.y];
    auto vl = sqrt(v[0]^^2 + v[1]^^2);
    auto vn = [v[0] / vl, v[1] / vl];
    auto vu = [-vn[1], vn[0]];
    auto vd = [vn[1], -vn[0]];
    auto p1 = Point(xm + vu[0] * h, ym + vu[1] * h);
    auto p2 = Point(xm + vd[0] * h, ym + vd[1] * h);
    return [p1, p2];
}



void scan(T...)(ref T args) {
    import std.stdio : readln;
    import std.algorithm : splitter;
    import std.conv : to;
    import std.range.primitives;

    auto line = readln().splitter();
    foreach (ref arg; args) {
        arg = line.front.to!(typeof(arg));
        line.popFront();
    }
    assert(line.empty);
}

void fillAll(R, T)(ref R arr, T value) {
    static if (is(typeof(arr[] = value))) {
        arr[] = value;
    }
    else {
        foreach (ref e; arr) {
            fillAll(e, value);
        }
    }
}

bool chmin(T, U...)(ref T x, U args) {
    bool isChanged;

    foreach (arg; args) {
        if (x > arg) {
            x = arg;
            isChanged = true;
        }
    }

    return isChanged;
}

bool chmax(T, U...)(ref T x, U args) {
    bool isChanged;

    foreach (arg; args) {
        if (x < arg) {
            x = arg;
            isChanged = true;
        }
    }

    return isChanged;
}
