#include <bits/stdc++.h>

using namespace std;

int main() {
    double ax, ay, az, bx, by,bz, cx, cy, cz;
    cin >> ax >> ay >> az >> bx >> by >> bz >> cx >> cy >> cz;
    double minX = min(bx, cx), maxX = max(bx, cx);
    double minY = min(by, cy), maxY = max(by, cy);
    double minZ = min(bz, cz), maxZ = max(bz, cz);
    double dx = 0, dy = 0, dz = 0;
    if (ax < minX) dx = minX - ax;
    else if (ax > maxX) dx = ax - maxX;
    if (ay < minY) dy = minY - ay;
    else if (ay > maxY) dy = ay - maxY;
    if (az < minZ) dz = minZ - az;
    else if (az > maxZ) dz = az - maxZ;

    double rastojanje = sqrt(dx*dx + dy*dy + dz*dz);

    cout << fixed << setprecision(4) << rastojanje << endl;

    return 0;
}