const int LG = 21;
const int FN = 400005;
const long long MOD = 1e9 + 7;
const long long INF = 1e9;
const long long INFLL = 1e18;

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<ll> vi;

#define forn(i, n) for (int (i) = 0; (i) != (n); (i)++)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define popcount(x) __builtin_popcount(x)
#define popcountll(x) __builtin_popcountll(x)
#define fi first
#define se second
#define re return
#define uniq(x) sort(all(x)); (x).resize(unique(all(x)) - (x).begin())

#ifdef LOCAL
#define dbg(x) cerr << __LINE__ << " " << #x << " " << x << endl
#define ln cerr << __LINE__ << endl
#else
#define dbg(x) void(0)
#define ln void(0)
#endif // LOCAL

int cx[4] = {-1, 0, 1, 0};
int cy[4] = {0, -1, 0, 1};

ll inq(ll x, ll y)
{
    if (!y) re 1 % MOD;
    ll l = inq(x, y / 2);
    if (y % 2) re l * l % MOD * x % MOD;
    re l * l % MOD;
}

ll rev(ll x)
{
    return inq(x, MOD - 2);
}

bool __precomputed_combinatorics = 0;
vector<ll> __fact, __ufact, __rev;

void __precompute_combinatorics()
{
    __precomputed_combinatorics = 1;
    __fact.resize(FN);
    __ufact.resize(FN);
    __rev.resize(FN);
    __rev[1] = 1;
    for (int i = 2; i < FN; i++) __rev[i] = MOD - __rev[MOD % i] * (MOD / i) % MOD;
    __fact[0] = 1, __ufact[0] = 1;
    for (int i = 1; i < FN; i++) __fact[i] = __fact[i - 1] * i % MOD, __ufact[i] = __ufact[i - 1] * __rev[i] % MOD;
}

ll fact(int x)
{
    if (!__precomputed_combinatorics) __precompute_combinatorics();
    return __fact[x];
}

ll cnk(int n, int k)
{
    if (k < 0 || k > n) return 0;
    if (!__precomputed_combinatorics) __precompute_combinatorics();
    return __fact[n] * __ufact[n - k] % MOD * __ufact[k] % MOD;
}

struct Point{
    double x, y;
};
struct Line{
    double a, b, c;
};
Point a, b, c;

double sqr(double x)
{
    return x * x;
}

double dist(Point a, Point b)
{
    return sqrt(sqr(a.x - b.x) + sqr(a.y - b.y));
}

Point Homo(Point a, Point b, double k)
{
    return Point{a.x + (b.x - a.x) * k, a.y + (b.y - a.y) * k};
}

Line Parallel(Point t, Point a, Point b)
{
    Line L;
    L.a = (a.y - b.y);
    L.b = (b.x - a.x);
    L.c = - L.a * t.x - L.b * t.y;
    return L;
}

Line Perpendicular(Point t, Point a, Point b)
{
    Line L;
    L.a = (a.y - b.y);
    L.b = (b.x - a.x);
    swap(L.a, L.b);
    L.a *= -1;
    L.c = - L.a * t.x - L.b * t.y;
    return L;
}

Point Cross(Line a, Line b)
{
    double y = (b.c * a.a - a.c * b.a) / (a.b * b.a - b.b * a.a);
    double x = (b.c * a.b - a.c * b.b) / (a.a * b.b - b.a * a.b);
    return Point{x, y};
}

double Incentre(Point a, Point b, Point c)
{
    double A = dist(b, c);
    double B = dist(a, c);
    double C = dist(a, b);
    Point p = Homo(a, c, C / (C + A));
    Point q = Homo(b, c, C / (C + B));
    Point i = Cross(Parallel(b, b, p), Parallel(a, a, q));
    Point h = Cross(Perpendicular(i, a, c), Parallel(a, a, c));
    return dist(i, h);
}

int ok(double r, Point a, Point b, Point c)
{
    double d = dist(a, b);
    if (d < 2 * r) return 0;
    Point k = Homo(a, b, r / d);
    Point l = Homo(b, a, r / d);
    Line p = Parallel(k, a, c);
    Line q = Parallel(l, b, c);
    Point m = Cross(p, q);
    double In = Incentre(k, l, m);
    if (In >= r) return 1;
    return 0;
}

int ok(double r)
{
    if (ok(r, a, b, c)) return 1;
    if (ok(r, b, c, a)) return 1;
    if (ok(r, c, a, b)) return 1;
    return 0;
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cout << setprecision(20) << endl;
    cin >> a.x >> a.y >> b.x >> b.y >> c.x >> c.y;
    double L = 0, R = 20040;
    for (int i = 0; i < 60; i++)
    {
        double M = (L + R) / 2;
        if (ok(M)) L = M;
        else R = M;
    }
    cout << L;
}

/* Note:
Check constants at the beginning of the code.
    N is set to 4e5 but be careful in problems with large constant factor.
    Setting N in every problem is more effective.
Check corner cases.
    N = 1
No def int long long for now.
Add something here.
*/


Measured memory_bytes: 256