#include "Windows.h"
#include <iostream>
#include <conio.h>
#include <cmath>
#include <vector>
#include <string>
#include <sstream>

using namespace std;


/**
 *  System Menu Do not Edit
 */

const int ENTER = 13;
const int UP = 72;
const int DOWN = 80;
#define MENU_DEFAULT_COLOR 10
#define MENU_ACTIVE_COLOR 14

struct MenuItem{
    string title;
    void (*func)();

    MenuItem(const string &title, void (*func)()) : title(title), func(func) {}
};


class Menu{

private:
    vector<MenuItem> items;
    int x0,y0;
    char ch;
    int selectedIndex, lastSelectedIndex;

    void gotoxy(int x, int y){
#ifdef WIN32
        COORD cur = {static_cast<SHORT>(x), static_cast<SHORT>(y)};
        SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), cur);
#else
        printf("\033[%dG\033[%dd", x+1, y+1);

#endif


    }
    void rect(int x1,int y1,int x2,int y2){
        int x,y;
        Menu::gotoxy(x1,y1); cout<<"É";
        Menu::gotoxy(x2,y1); cout<<"»";
        Menu::gotoxy(x1,y2); cout<<"È";
        Menu::gotoxy(x2,y2); cout<<"¼";
        for(x=x1+1;x<x2;x++)
        {
            Menu::gotoxy(x,y1); cout<<"Í";
            Menu::gotoxy(x,y2); cout<<"Í";
        }
        for(y=y1+1;y<y2;y++)
        {
            Menu::gotoxy(x1,y); cout<<"º";
            Menu::gotoxy(x2,y); cout<<"º";
        }
    }


public:

    Menu() {
        lastSelectedIndex = 0;
        selectedIndex = 0;
        x0 = 5;
        y0 = 5;
    }

    const vector<MenuItem> &getItems() const {
        return items;
    }

    void add(const string& title,  void (*func)()){
        MenuItem item(title, func);
        Menu::items.push_back(item);
    }

    void next(){
        lastSelectedIndex = selectedIndex;
        selectedIndex ++;
        if(selectedIndex > (int)items.size() -1){
            selectedIndex = 0;
        }

        Menu::writeItem(lastSelectedIndex, MENU_DEFAULT_COLOR);
        Menu::writeItem(selectedIndex, MENU_ACTIVE_COLOR);
    }
    void prev(){
        lastSelectedIndex = selectedIndex;
        selectedIndex --;
        if(selectedIndex < 0){
            selectedIndex = (int) items.size() -1;
        }

        Menu::writeItem(lastSelectedIndex, MENU_DEFAULT_COLOR);
        Menu::writeItem(selectedIndex, MENU_ACTIVE_COLOR);
    }

    int textColor(int Color)
    {
        HANDLE h;
        h = GetStdHandle(STD_OUTPUT_HANDLE);
        return SetConsoleTextAttribute(h, Color);
    }

    void write(const string& s, int x, int y, int color){
        textColor(color);
        Menu::gotoxy(x,y); cout<<s;
        textColor(15);
    }

    void writeItem(int index, int color){
        string prefix = Menu::to_string(index+1) + ". ";
        Menu::write(prefix + items[index].title, x0, y0 + index, color);
    }

    string to_string(int i){

        std::stringstream ss;
        ss << i;
        return ss.str();
    }
    void select(int index){

        system("cls");
        Menu::rect(x0-2,y0-1,x0+35,y0+(int)Menu::items.size());
        for(int i=0;i<items.size();i++){
            if(i==index) {
                Menu::write(Menu::to_string(i) + ". " + items[i].title,x0,y0+i,MENU_ACTIVE_COLOR);
                Menu::writeItem(i, MENU_ACTIVE_COLOR);
            }
            else {
                Menu::writeItem(i, MENU_DEFAULT_COLOR);
            }
        }

        Menu::copyright();

    }

    void copyright(){
        Menu::write("Copyright (c) 2019 by Pham Anh Phuong.",x0-4,y0+(int)items.size()+5,10);
        Menu::write("Danh sach nhom:",x0+40,y0,14);
        Menu::write("1. Nguyen Dinh Toan",x0+40,y0+1,14);
    }

    void render(){

        system("cls");

        selectedIndex = 0; // default menu selection.
        lastSelectedIndex = 0;
        Menu::select(0);
        bool ok = false;
        do{
            ch = getch();
            switch ((int)ch){

                case UP:
                    Menu::prev();
                    break;

                case DOWN:
                    Menu::next();
                    break;

                case ENTER:
                    // execute select menu item

                   system("cls");
                   Menu::items[selectedIndex].func();
                   cout << endl << "Press Enter to exit.";
                   getch();
                   Menu::select(selectedIndex);


                    break;


                default:

                    break;
            }




        }while (ch != 27);

    }
};
/**
 * End System Menu do not edit above;
 */




 struct Multiply {

	struct Row {
		vector<int> v;
	};

        vector<Row> rows;
        vector<int> v1, v2;

        Multiply(string s1, string s2) {

            for (int i = 0; i < s1.size(); ++i) {
                Multiply::v1.push_back(s1[i] - '0');
            }
            for (int i = 0; i < s2.size(); ++i) {
                Multiply::v2.push_back(s2[i] - '0');
            }

        }

        Multiply *calculate() {

            if (v1.empty() || v2.empty()) {
                return this;
            }


            int level = 0;

            for (int i = v2.size() - 1; i >= 0; --i) {
                int carry = 0;
                Row row;
                for (int k = 0; k < level; ++k) {
                    row.v.push_back(0);
                }
                for (int j = v1.size() - 1; j >= 0; --j) {
                    int value = v1[j] * v2[i] + carry;
                    row.v.push_back(value % 10);
                    carry = value / 10;
                }
                if (carry > 0) {
                    row.v.push_back(carry);
                }
                rows.push_back(row);
                level++;


            }

            // cong cac hang lai voi nhau
            int maxSize = 1;
            for (int i = 0; i < rows.size(); ++i) {
                if (rows[i].v.size() > maxSize) {
                    maxSize = rows[i].v.size();
                }
            }

            // tao matran dong cot maxSize
           //int arr[maxSize][maxSize];
            vector<vector<int> > arr(maxSize, vector<int> (maxSize, 0));

            for (int i = 0; i < rows.size(); ++i) {
                Row row = rows[i];
                for (int j = 0; j < row.v.size(); ++j) {
                    arr[i][j] = row.v[j];
                }
            }


            vector<int> result;
            int carry = 0;

            for (int column = 0; column < maxSize; ++column) {
                int value = 0;
                for (int row = 0; row < maxSize; ++row) {
                    value += arr[row][column];
                }
                value += carry;
                result.push_back(value %10);
                carry = value /10;

            }
            if(carry > 0){
                result.push_back(carry);
            }


            // output
            for (int i = 0; i < result.size() - v1.size(); ++i) {
                cout << "  ";
            }

            for (int i = 0; i < v1.size(); ++i) {
                cout << v1[i] << " ";
            }

            cout << endl;
            for (int i = 0; i < result.size(); ++i) {
                if(i == 0){
                    cout << "* ";
                }else{
                    cout << " ";
                }
            }

            cout << endl;

            for (int i = 0; i < result.size() - v2.size(); ++i) {
                cout << "  ";
            }

            for (int i = 0; i < v2.size(); ++i) {
                cout << v2[i] << " ";
            }
            cout << endl;
            for (int i = 0; i < maxSize; ++i) {
                cout << "--" ;
            }
            cout << endl;
            for (int i = result.size() -1; i >= 0; --i) {
                cout << result[i] <<" ";
            }

            return this;


        }

    };

void phep_nhan_cach_1(){

    Multiply *multiply = new Multiply("567", "1234");
    multiply->calculate();

}

int main()
{

    Menu menu;
    menu.add("Phep Nhan Cach 1", phep_nhan_cach_1);
    menu.render();

    return 0;
}