MatrixMult

#include <iostream>
#include <vector>
#include <string>
#include <cmath>
using namespace std;

bool EnterVector(vector<int>&);//This function read ouк vector from input stream
void PrintVector(const vector<int>& ourVector); //This function print our vector
void PrintMatrix(const vector<vector<int>>& lhs); //This function print matrix


vector<int> FirstVector(3);
vector<int> SecondVector(3);
int mul_num = 0;

//User function for operation

vector<int> Sum(const vector<int>& lhs, const vector<int>& rhs);
vector<int> MulNum(const vector<int>& lhs, const int& rhs);
vector<int> MulScalar(const vector<int>& lhs, const vector<int>& rhs);
vector<int> MulVector(const vector<int>& lhs, const vector<int>& rhs);
vector<int> Abs(const vector<int>& lhs);
bool isEqual(const vector<int>& lhs, const vector<int>& rhs);





int main() {
    for (;;) {
        size_t operation = ' ';

        cout << "Enter the operation\n";
        //TODO: add help

        cin >> operation;

        switch (operation) {
        case 0:
            EnterVector(FirstVector);
            EnterVector(SecondVector);
            PrintVector(Sum(FirstVector, SecondVector));

            break;
        case 1:
            EnterVector(FirstVector);
            cin >> mul_num;
            PrintVector(MulNum(FirstVector, mul_num));
            break;

        case 2:
            EnterVector(FirstVector);
            EnterVector(SecondVector);
            PrintVector(MulScalar(FirstVector, SecondVector));
            break;

        case 3:
            EnterVector(FirstVector);
            EnterVector(SecondVector);
            PrintVector(MulVector(FirstVector, SecondVector));
            break;

        case 4:
            EnterVector(FirstVector);
            PrintVector(Abs(FirstVector));
            break;

        case 5:
            EnterVector(FirstVector);
            EnterVector(SecondVector);
            if (isEqual) {
                cout << "Is equal\n";
            }
            else {
                cout << "Isn't equal\n";
            }
            break;

        default:
            cout << "Undefined operation\n";
            break;
        }
    }
    return 0;
}



bool EnterVector(vector<int>& ourVector){
    cout << "Enter vector\n";
    for (auto& s : ourVector) {
        cin >> s;
    }
    return true;
}

void PrintVector(const vector<int>& ourVector){
    for (const auto& s : ourVector) {
        cout << s << ' ';
    }
}

void PrintMatrix(const vector<vector<int>>& lhs) {
    for (const auto& i : lhs) {
        for (const auto& j : i) {
            cout << j << ' ';
        }
        cout << '\n';
    }
}

vector<int> Sum(const vector<int>& lhs, const vector<int>& rhs) {
    vector<int> result = { lhs.at(0) + rhs.at(0), lhs.at(1) + rhs.at(1), lhs.at(2) + rhs.at(2) };
    return (vector<int>) result;
}

vector<int> MulNum(const vector<int>& lhs, const int& rhs) {
    vector<int> result= { lhs.at(0) * rhs, lhs.at(1) * rhs, lhs.at(2) * rhs };
    return result;
}

vector<int> MulScalar(const vector<int>& lhs, const vector<int>& rhs) {
    vector<int> result = { lhs.at(0) * rhs.at(0), lhs.at(1) * rhs.at(1), lhs.at(2) * rhs.at(2) };
    return result;
}


vector<int> MulVector(const vector<int>& lhs, const vector<int>& rhs) {
    vector<int> result = { (lhs.at(0) * rhs.at(2) - lhs.at(1)*rhs.at(0), (lhs.at(0) * rhs.at(2) - rhs.at(0) * lhs.at(2)), (lhs.at(0)*rhs.at(1) - rhs.at(0) * lhs.at(1)))};
    return result;
}

vector<int> Abs(const vector<int>& lhs) {
    vector<int> result = { abs(lhs.at(0)), abs(lhs.at(1)), abs(lhs.at(2)) };
    return result;
}

bool isEqual(const vector<int>& lhs, const vector<int>& rhs) {
    bool result = true;
    for (int i = 0; i < 3; ++i) {
        result &= lhs.at(i) == rhs.at(i);
    }
    return result;
}