Vec3 P1

#include <iostream>

using namespace std;

struct Vec3 {

    float x,y,z;
    Vec3(float x,float y,float z):x(x),y(y),z(z) {}
    friend ostream& operator<<(ostream&o,const Vec3& x) {
       o<<"("<<x.x<<", "<<x.y<<", "<<x.z<<")";
        return o;
    }
};
float Dot(Vec3 v1, Vec3 v2) {
    return v1.x*v2.x + v1.y*v2.y + v1.z*v2.z;
}
Vec3 Cross(Vec3 v1, Vec3 v2) {
    return Vec3(v1.y*v2.z-v2.y*v1.z, v1.z*v2.x-v1.x*v2.z,v1.x*v2.y-v1.y*v2.x);
}



int main() {
    std::cout << Dot(Vec3(1,0,0),Vec3(0,1,0)) << std::endl;
    return 0;
}