#include <iostream>
using namespace std;

double sumOf(double n)
{
    double i, sum = 0;

    for (i = 1; i <= n; i++)
    {
        sum += (1 / (i*i));
    }

    return sum;
}

void printDiv()
{
    int i, sum;
    for (i = 2; i < 1000; i++)
    {
        if (i < 10)
        {
            cout << i << ",";
        }
        else if (i >= 10 && i < 100)
        {
            sum = (i % 10) + (i / 10);
            if (i%sum == 0)
                cout << i << ",";
        }
        else
        {
            sum = (i % 10) + ((i / 10) % 10) + (i / 100);
            if (i%sum == 0)
                cout << i << ",";
        }
    }
}

void math(int a, int n)
{
    int sum, i, factor;

    if (a == 1)
    {
        sum = 0;
        for (i = 0; i < 10; i++)
        {
            sum = sum + n;
            cout << sum << ",";
        }
    }
    if (a == 2)
    {
        cout << "Enter Factor";
        cin >> factor;
        for (i = 0; i < 10; i++) {
            cout << n << " ";
            n = n*factor;
        }
    }
}

double power(double a, double b)
{
    double i, res = 1;
    for (i = 0; i < b; i++)
    {
        res = res*a;
    }
    return res;
}

double azeret(double a)
{
    double res = 1, i;
    for (i = 1; i <= a; i++)
    {
        res = res*i;
    }
    return res;
}

double func(double n, double x)
{
    double i, sum = 0;

    sum = 1 + x;
    cout << "1 + " << x;
    for (i = 2; i < n; i++) {
        cout << "+";
        cout << power(x, i) << "/" << azeret(i);
        sum = sum + power(x, i) / azeret(i);
    }
    cout << "=";
    return sum;
}


int main()
{
    int x, num1, num2, num3;
    double num4, num5;
    do
    {
        cout << "0 - EXIT\n1.for sum of 1/n^2\n2.for print numbers that are divided by sum of digits\n3.for print arithmetic or geometric progression\n4.for Tylor series\n";
        cin >> x;
        if (x == 1)
        {
            cout << "Enter number: ";
            cin >> num1;
            cout << sumOf(num1) << "\n";
        }
        else if (x == 2)
        {
            printDiv();
        }
        else if (x == 3)
        {
            cout << "Enter Action Number: ";
            cin >> num2;
            cout << "Enter Number: ";
            cin >> num3;
            math(num2, num3);
        }
        else if (x == 4)
        {
            cout << "Enter N: ";
            cin >> num4;
            cout << "Enter X: ";
            cin >> num5;
            cout << func(num4, num5) << "\n";

        }

    }
    while (x != 0);
    cout << "THE END\n";

    return 0;
}