小程序结构

#include <iostream>

using namespace std;

int main()
{
    // 控制结构：顺序结构、选择结构和循环结构
    // 选择结构：if单选、if...else双选和switch多选结构
    // 循环结构：while、for、do...while
    // 三个语句：break、continue和goto
    // 两种连接控制结构的方式：嵌套和堆叠

    cout << "********************************************************" << endl;
    cout << "*                     Welcome   　　　　　　　　　　　 *" << endl;
    cout << "*           1 to Leap Year Judging                     *" << endl;
    cout << "*           2 to Palindromic Judging                   *" << endl;
    cout << "*           3 to Date Judging                          *" << endl;
    cout << "*           0 to Exit the app                          *" << endl;
    cout << "********************************************************" << endl;

    int choice;
    cout << "Welcome to the Games, 0 to exit,(1-3) to the Game!\n";
    cin >> choice;

    while(choice)
    {
        if(0==choice)
        {
            return 0;
        }
        if(1==choice)
        {
            // Leap year
            int year;
            int selection;
            cout << "Welcome to Leap Year Judging App!" << endl;
            cout << " 1 to continue, 0 to exit: ";
            cin >> selection;

            while(selection)
            {
                cout << "Input a year: ";
                cin >> year;

                if( ( 0==year%400 )||( 0!=year%100 && 0==year%4) )
                {
                    cout << "Year:" << year << " is a leap year " << endl;
                }
                else
                {
                    cout << "Year:" << year << " is not a leap year " << endl;
                }

                cout << "Welcome to Leap Year Judging App again!" << endl;
                cout << " 1 to continue, 0 to exit: ";
                cin >> selection;
            }
        }
        if(2==choice)
        {
            // Palindromic, 5digits
            int num;
            int selection;
            cout << "Welcome to Palindromic Judging App!" << endl;
            cout << " 1 to continue, 0 to exit: ";
            cin >> selection;

            while(selection)
            {
                cout << "Input a num: ";
                cin >> num;
                // 12321 12345
                if( ( num/10000==num%10 )||( num%10000/1000==num%100/10) )
                {
                    cout << "Number:" << num << " is a Palindromic number " << endl;
                }
                else
                {
                    cout << "Number:" << num << " is not a Palindromic number " << endl;
                }

                cout << "Welcome to Palindromic Judging App again!" << endl;
                cout << " 1 to continue, 0 to exit: ";
                cin >> selection;
            }
        }
        if(3==choice)
        {
            // Date
            int month, day, year;
            int dayth=0;
            int selection;
            cout << "Welcome to Date Judging App!" << endl;
            cout << " 1 to continue, 0 to exit: ";
            cin >> selection;

            while(selection)
            {
                cout << "Input a Date: ";
                cin >> month >> day >> year;

                int Days[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};

                if( ( 0==year%400 )||( 0!=year%100 && 0==year%4) )
                {
                    Days[2]++;
                }

                for(int i=1; i<month; i++)
                {
                    dayth += Days[i];
                }

                dayth += day;
                cout << "Date: " << month << ", " << day << " " << year
                     << " is the " << dayth << "th day in the year: " << year << endl;

                cout << "Welcome to Leap Year Judging App again!" << endl;
                cout << " 1 to continue, 0 to exit: ";
                cin >> selection;
            }
        }
        if(4==choice)
        {
            // new function
        }

        cout << "********************************************************" << endl;
        cout << "*                     Welcome   　　　　　　　　　　　 *" << endl;
        cout << "*           1 to Leap Year Judging                     *" << endl;
        cout << "*           2 to Palindromic Judging                   *" << endl;
        cout << "*           3 to Date Judging                          *" << endl;
        cout << "*           0 to Exit the app                          *" << endl;
        cout << "********************************************************" << endl;

        //int choice;// the inner choice hided the outer choice
        cout << "Welcome to the Games, 0 to exit,(1-3) to the Game!\n";
        cin >> choice;
    }





    return 0;
}