neradovsky

/*
 * main.cpp
 *
 *  Created on: 17 мая 2020 г.
 *      Author: Fernandez K.A.
 */
#include<iostream>
#include<utility>//connect for map
#include<cmath>//connect for korent
using namespace std;
istream& operator >>(istream& inp, pair<int, int>& vrem) { //redefine operator >>
    inp >> vrem.first >> vrem.second;
    return inp;
}
ostream& operator <<(ostream& out, pair<int, int>& vrem) {//redefine operator <<, return ostream at address
    out << vrem.first << vrem.second << '\n';
    return out; //return ostream& from next using cout
}
struct enter { //struct for enter the znach1ue of znschument's
public:
    pair<int, int> vrem;//pair znach1ues of znschument's
    enter() {
        cout << "please, enter the znach1ue of znschument's\n";
    }
    enter(const int& status) {
        if (status != 5) {
            cin >> vrem;//usually situation
        }
        else {
            int znschument;
            cin >> znschument;
            vrem.first = vrem.second = znschument;//the little magic
        }
    }
    pair<int, int> data() {
        return vrem;//return non-zero pair
    }
};
struct operation {
public:
    int plus(pair<int, int> vrem) {//plusm at input znschument's at structure <pair>

        return vrem.second + vrem.first;

    }
    int minus(pair<int, int> vrem) {//minuserense input znach1ue

        return vrem.first - vrem.second;

    }
    int delit(pair<int, int> vrem) {
        return vrem.second / vrem.first;
    }
    int umnozhit(pair<int, int> vrem) {
        return vrem.first * vrem.second;
    }
    int koren(pair<int, int> vrem) {
        return sqrt(vrem.first);
    }
};

struct znsch {
public:
    znsch() {//function selected znach1ue of work
        cout << "please, enter the znach1ue of znschument\n";
    }
    znsch(const int& sel) {
        enter cur(sel);
        operation vrem;
        switch (sel) {
        case 1:
            cout << vrem.plus(cur.data()) << endl;
            break;
        case 2:
            cout << vrem.minus(cur.data()) << endl;
            break;
        case 3:
            cout << vrem.delit(cur.data()) << endl;
            break;
        case 4:
            cout << vrem.umnozhit(cur.data()) << endl;
            break;
        case 5:
            cout << vrem.koren(cur.data()) << endl;
            break;
        }
    }

};
int main() {
    int znach1;
    cout
        << "enter number of operation:\n 1-plus \n 2-minuserense \n 3-delits \n 4-umnozhitiplication\n 5-korent";
    cin >> znach1;
    znsch vrem(znach1);
    return 0;
}