//goldemerald's prime numbers program
//i do not know how to use binary or new line stuff :P

// Required if your program does any I/O
#include <iostream>
#include <iomanip>
#include <string>
#include <cstring>
// Required for ANSI C++ 1998 standard.
using namespace std;

void decision();
void myNumber();
void morePrimeNumbers(int &count);
void reset(int &count);

int main()
{
    cout << "goldemerald's prime number program" << endl;
    decision();
    system("pause");
    return 0;
}

void decision()
{
    char decide;
    int count = 1;

    cout << "What would you like to do: " << endl;
    cout << "See if a number is a prime number, press 'A'; See if numbers are prime in a row, press 'B'; Reset seen prime numbers to 0, press 'C'; Or press 'Q' to quit: ";
    cin >> decide;
    while (decide != 'Q')
    {
        if (decide == 'A')
            myNumber();
        if (decide == 'B')
            morePrimeNumbers(count);
        if (decide == 'C')
            reset(count);
        cout << "See if a number is a prime number, press 'A'; See if numbers are prime in a row, press 'B'; Reset seen prime numbers to 0, press 'C'; Or press 'Q' to quit: ";
    }
}

void myNumber()
{
    int number;
    int increase = 1;
    double x;
    string answer;
    answer = "yes";

    cout << "What is the number you want to check if it's a prime number?" << endl;
    cin >> number;

    while (increase < number)
    {
        //ensures that 1 is not used for number or increase
        x = number/increase;
        //sees if the number has a remainder, if no, the number is not prime
        if ((number%increase) == 0 && x != 1 && x != number)
            answer = "no";
        //tells the user their number is not prime
        if (answer == "no")
        {
            cout << answer << " it is not a prime number!" << endl;
            return;
        }
        //increases the divisor by 1 to see if the next integer increased will have a remainder
        increase++;
    }
    //if the number always has a remainder, it tells the user it's a prime number
    cout << answer << " it is a factor!" << endl;
}
void morePrimeNumbers(int &count)
{
    int x;
    int y;
    int increase = 1;
    //j is a binary set to false, but i dont know how to use those :P
    int j = 0;
    int input;

    cout << "How many (more) prime numbers would you like to see? ";
    cin >> input;

    //sets x to be the number of factors to be seen to the users input plus, starting from 1 or the last place left off
    x=count + input;
    cout << "Here are the next " << input << " prime numbers:" << endl;
    //a loop to show the numbers from start to the input number
    while (count < x)
    {
        //the increasing number that will be dividing the next number(count) to see if there is a remainder
        while (increase < count && j != 1)
        {
            y = count/increase;
            //if the number can be divided, it tells the user
            if (count%increase == 0 && y != 1 && y != count)
            {
                cout << count << "is not a factor!" << endl;
                //sets the binary number to true for later use
                j = 1;
            }
            //increases the divisor to see if the next number up can divide it
            increase++;
        }
        //resets the divisor
        increase = 1;

        //if the binary number is false, tell the user the number is a prime number
        if (j==0)
            cout << count << "is a factor!" << endl;
        //resets the binary number to false
        j=0;
        //now we move up to the next number
        count++;
    }
}
void reset(int &count)
{
    count = 1;
    cout << "It has been reset to 1!" << endl;
}