new

#include <iostream>
using namespace std;
int main()
{
    float a, b, cnt = 3;
    int c, d;
    float sum = 0;
    cout << "Simple calculator" << endl;
    cout << "1 number:";
    cin >> a;
    cout << "2 number:";
    cin >> b;
    cout << "How to calculate?" << endl;
again:
    cout << "1:+  2:-  3:×  4:÷" << endl;
    cin >> c;
    if (c == 1)
    {
        sum = a + b;
        cout << a << "+" << b << "=" << sum << endl;
    }
    else if (c == 2)
    {
        sum = a - b;
        cout << a << "-" << b << "=" << sum << endl;
    }
    else if (c == 3)
    {
        sum = a * b;
        cout << a << "×" << b << "=" << sum << endl;
    }
    else if (c == 4)
    {
        sum = a / b;
        cout << a << "÷" << b << "=" << sum << endl;
    }
    else
    {
        cout << "An unexpected error occurred" << endl;
        cout << "Please re-enter the calculate method" << endl;
        goto again;
    }
    c = 0;
    while (1)
    {
        cout << cnt << " nember:";
        cin >> d;
        cout << "How to calculate?" << endl;
    again1:
        cout << "1:+  2:-  3:×  4:÷" << endl;
        cin >> c;
        if (c == 1)
        {
            sum = sum + d;
            cout << sum - d << "+" << d << "=" << sum << endl;
        }
        else if (c == 2)
        {
            sum = sum - d;
            cout << sum << "-" << d << "=" << sum << endl;
        }
        else if (c == 3)
        {
            sum = sum * d;
            cout << sum << "×" << d << "=" << sum << endl;
        }
        else if (c == 4)
        {
            sum = sum / d;
            cout << sum << "÷" << d << "=" << sum << endl;
        }
        else
        {
            cout << "An unexpected error occurred" << endl;
            cout << "Please re-enter the calculate method" << endl;
            goto again1;
        }
        cnt++;
    }
    return 0;
}