include iostream include vector include algorithm using namespace std

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#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
double const E = 0.001;
int const INF = 1000;
double d;
struct Point
{
double x;
double y;
double z;
double Vx;
double Vy;
double Vz;
};
vector<Point> q;
double f(Point a, Point b,double t)
{
a.x += a.Vx*t; b.x += b.Vx*t;
a.y += a.Vy*t; b.y += b.Vy*t;
a.z += a.Vz*t; b.z += b.Vz*t;
return max((a.x - b.x)*(a.x - b.x) + (a.y - b.y)*(a.y - b.y) + (a.z - b.z)*(a.z - b.z) , d );
}
double tern(Point a, Point b)
{
double l = 0;
double r = INF;
while (r - l > E)
{
double ml = (r + l) / 3 + l;
double mr = 2 * (l + r) / 3 + l;
if ( f(a, b, ml) > f(a, b, mr) )
l = ml;
else
r = mr;
}
return l;
}
int main()
{
int n;
cin >> n >> d;
q.resize(n);
vector<double> rez;
for (int i = 0; i < n; ++i)
{
cin >> q[i].x >> q[i].y >> q[i].z >> q[i].Vx >> q[i].Vy >> q[i].Vz;
}
double c;
for (int j = 0; j < n - 1; ++j)
{
for (int k = j + 1; k < n; ++k)
{
c = tern(q[j], q[k]);
if (c != 0 && c != INF)
rez.push_back(c);
}
}
c = INF;
if (rez.size() == 0)
cout << "OK" << endl;
else
{
for (int i = 0; i < rez.size(); ++i)
{
if (rez[i] < c)
c = rez[i];
}
cout << "ALARM!" << endl << c << endl;
}
return 0;
}