//---------------------------------------------------------------------------

#pragma hdrstop
#include <iostream.h>
const int SIZE = 50;

//---------------------------------------------------------------------------

struct TVec{
        float Vec[SIZE];
        int size;
};

float operator* (TVec v1, TVec v2){
        if(v1.size != v2.size){
                cerr << "Error!!!" << endl;
                return 0;
        }
        float rez = 0;
        for(int i = 0; i < v1.size; i++){
                rez += v1.Vec[i] * v2.Vec[i];
        }
        return rez;
}

TVec operator+ (TVec v1, TVec v2){
        TVec rez;
        (v1.size > v2.size) ? rez.size = v1.size : rez.size = v2.size;

        for(int i = 0; i < rez.size; i++){
                rez.Vec[i] = v1.Vec[i] + v2.Vec[i];
        }
        return rez;
}

TVec operator- (TVec v1, TVec v2){
        TVec rez;
        (v1.size > v2.size) ? rez.size = v1.size : rez.size = v2.size;

        for(int i = 0; i < rez.size; i++){
                rez.Vec[i] = v1.Vec[i] - v2.Vec[i];
        }
        return rez;
}

istream& operator>> (istream &is, TVec &v){
        for(int i = 0; i < v.size; i++){
                is >> v.Vec[i];
        }
        return is;
}

ostream& operator<< (ostream &os, TVec v){
        os << "(";
        for(int i = 0; i < v.size; i++){
                os << v.Vec[i];
                if(i < v.size - 1) os << "; ";
        }
        os << ")" << endl;
        return os;
}

#pragma argsused
int main(int argc, char* argv[])
{
        int n;
        TVec v1, v2;

        cout << "Enter size of first vector: ";
        cin >> n;
        v1.size = n;

        cout << "Enter size of second vector: ";
        cin >> n;
        v2.size = n;

        cout << "Enter v1: " << endl;
        cin >> v1;
        cout << "Enter v2: " << endl;
        cin >> v2;

        TVec S = v1 + v2, R = v1 - v2;

        cout << "Suma vectoriv: " << S;
        cout << "Riznitsa vectoriv: " << R;
        cout << "Mnojenia = " << v1 * v2 << endl;
        cout << "d = " << S * R;
        //d=(a+b)(a-b)

        cin.get();
        cin.get();
        return 0;
}
//---------------------------------------------------------------------------