// for functions rand and srand
#include
//
#include
// input/output stream
#include
// for function time, and for data type time_t
#include
//
#include

using namespace std;

const float M_2PIf = 6.283185307179586476925286766559f;
const float M_PIf  = 3.141592653589793238462643383279f;

/* ——————————————————————– */

bool init_rnd()
{
    time_t TIME;
    ctime(&TIME);
    srand48((unsigned int)(TIME));
    return true;
}

// Random szamokat general egyenletes eloszlassal (az [a,b[ intervallumon):
double uniform(double a, double b)
{
    return a+(b-a)*drand48();
}

/* ——————————————————————– */

struct vektor {
float x,y,z;
};

class Matrix3x3 {
private:
float tomb[3][3];

public:
void Matrix::init(vektor &a, vektor &b){
    tomb[0][0] = a.x*b.x;
    tomb[1][0] = a.x*b.y;
    tomb[2][0] = a.x*b.z;
    tomb[0][1] = a.y*b.x;
    tomb[1][1] = a.y*b.y;
    tomb[2][1] = a.y*b.z;
    tomb[0][2] = a.z*b.x;
    tomb[1][2] = a.z*b.y;
    tomb[2][2] = a.z*b.z;
}

Matrix3x3 &operator +=(Matrix3x3 b){
int x,y;
for(x=0; x<3; x++)
for(y=0; y<3; y++)
  tomb[x][y] += b.tomb[x][y];
return *this;
}

Matrix3x3 &operator/=(float c){
int x,y;
for(x=0; x<3; x++)
for(y=0; y<3; y++)
  tomb[x][y] /= c;
return *this;
}

};

/* ——————————————————————– */

int main() {

vektor tar[10];   

int i;

for (i=0;i<10;i++) {

   
    float phi  = uniform(0.0f, M_2PIf);
  float costheta = uniform(-1.0f, 1.0f);
   
    float x = 1.0f * sqrtf(1-costheta*costheta) * cosf(phi);
    float y = 1.0f * sqrtf(1-costheta*costheta) * sinf(phi);
    float z = 1.0f * costheta;

  //cout << x << " " << y << " " << z << endl;

    tar[i].x = x;
    tar[i].y = y;
    tar[i].z = z;

    }

/* ——————————————————————– */
Matrix tar[10];

for(i=0; i<10; i++)
tar[i].init(tar[i]);

Matrix osszeg = tar[0];

for(i=1; i<10; i++)
osszeg += tar[i];

/* ——————————————————————– */

return 0;
}