#include <iostream>
#include <random>
#include <vector>

using namespace std;

int get_random_number(int a, int b)
{
    random_device rd;
    mt19937 gen(rd());
    uniform_int_distribution<> distrib(a, b);
    int random_number = distrib(gen);
    return random_number;
}

int main()
{
    int test_time = 0, right_door = 0, right_time = 0, choose_door = 0, open_door = 0;
    double sum = 0;
    vector<int> wait_open_door;
    cout << "请输入测试次数" << endl;
    cin >> test_time;
    cout << "第一次测试：不更改门";
    for (int cptime = 1; cptime <= test_time; cptime++)
    {
        right_door = get_random_number(1, 3);
        choose_door = get_random_number(1, 3);
        if (right_door == choose_door)
        {
            wait_open_door.clear();
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != choose_door)
                {
                    wait_open_door.push_back(ncptime);
                }
            }
            open_door = wait_open_door[get_random_number(0, wait_open_door.size() - 1)];
            right_time++;
        }
        else if (right_door != choose_door)
        {
            wait_open_door.clear();
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != choose_door && ncptime != right_door)
                {
                    open_door = ncptime;
                }
            }
        }
    }
    sum = static_cast<double>(right_time) / static_cast<double>(test_time);
    cout << "测试完毕。" << endl << "测试次数：" << test_time << endl << "概率为：" << sum << endl;
    cout << "第二次测试：更改门";
    sum = 0, right_door = 0, right_time = 0, choose_door = 0, open_door = 0;
    wait_open_door.clear();
    for (int cptime = 1; cptime <= test_time; cptime++)
    {
        right_door = get_random_number(1, 3);
        choose_door = get_random_number(1, 3);
        if (right_door == choose_door)
        {
            wait_open_door.clear();
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != choose_door)
                {
                    wait_open_door.push_back(ncptime);
                }
            }
            open_door = wait_open_door[get_random_number(0, wait_open_door.size() - 1)];
            int temp = 0;
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != choose_door && ncptime != open_door)
                {
                    temp = ncptime;
                }
            }
            choose_door = temp;
        }
        else if (right_door != choose_door)
        {
            wait_open_door.clear();
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != right_door && ncptime != choose_door)
                {
                    open_door = ncptime;
                }
            }
            int temp = 0;
            for (int ncptime = 1; ncptime <= 3; ncptime++)
            {
                if (ncptime != choose_door && ncptime != open_door)
                {
                    temp = ncptime;
                }
            }
            choose_door = temp;
        }
        if (choose_door == right_door)
        {
            right_time++;
        }
    }
    sum = static_cast<double>(right_time) / static_cast<double>(test_time);
    cout << "测试完毕。" << endl << "测试次数：" << test_time << endl << "概率为：" << sum << endl;
}