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        //6.1
#include <iostream>
#include <cctype>
#include <string>
#include <fstream>
#include <cstdlib>
using namespace std;
const int strsize = 128;
struct bop
{
    char fullname[strsize];
    char title[strsize];
    char bopname[strsize];
    int preference;
};
        //6.1
int P6_1(void)
{
    using namespace std;
    char ch;
    while ((ch = cin.get()) != '@')
    {
        if(isdigit(ch))
            continue;
        else if(islower(ch))
            cout << (char)toupper(ch) ;
        else if (isupper(ch))
            cout << (char)tolower(ch) ;
    }

    return 0;
}
        //6.2
int P6_2(void)
{
    double donation[10];
    double sum = 0, ave;
    int count = 0, clarger = 0;

    while (count<10 && cin >> donation[count])
    {
        sum += donation[count];
        ++count;
    }
    ave = sum / count;
    cout << "You have entered " << count << " numbers.\n";
    cout << "sum = " << sum << endl;
    cout << "average = " << ave << endl;
    for ( int i =0; i<count; i++ )
    {
        if(donation[i]>ave)
            ++clarger;
    }
    cout << "There are " << clarger << " number(s) lager than average value.\n";
    return 0;
}
        //6.3
int P6_3(void)
{
    char ch;

    cout << "Please enter one of the following choices: \n";
    cout << "c) carnivore" "p) pianist\n";
    cout << "t) tree             g) game\n";
    cout << "Please enter a c, p, t or g: ";
    while (cin.get(ch))
    {
        cin.get();
        switch(ch)
        {
            case 'c' : cout << "Tiger is a carnivore.\n"; break;
            case 'p' : cout << "Mozart is a pianist.\n"; break;
            case 't' : cout << "A maple is a tree.\n"; break;
            case 'g' : cout << "GTA is a game.\n"; break;
        }
        cout << "Please enter a c, p, t or g: ";
    }
    return 0;
}
        //6.4
void P6_4()
{
    bop datbop[5] = {
        {"Wimp Macho", "123", "zhangsan", 2},
        {"Raki Rhodes", "456","lisi", 1},
        {"Celia Laiter", "789", "wangwu", 0},
        {"Hoppy Hipman", "234", "zhaoliu", 2},
        {"Pat Hand", "567", "chenqi", 1},
        };
    int i = 0;
    int exit = 0;
    cout << "Benevolent Order of Programmers Report\n";
    cout << "a. display by name         b. display by title\n";
    cout << "c. displea by bopname      d. display by preference\nq. quit\n";
    char ch;
    cout << "Enter your choice: ";

    while(cin.get(ch))
    {
        cin.get();
        switch(ch)
        {
        case 'a':
            for(i=0; i<5; i++)
                cout << datbop[i].fullname << endl;
                break;
        case 'b':
            for(i=0; i<5; i++)
                cout << datbop[i].title << endl;
            break;
        case 'c':
            for(i=0; i<5; i++)
                cout << datbop[i].bopname << endl;
            break;
        case 'd':
            for(i=0; i<5; i++)
            {
                if (datbop[i].preference==0)
                    cout << datbop[i].fullname << endl;
                else if (datbop[i].preference==1)
                    cout << datbop[i].title << endl;
                else if (datbop[i].preference==2)
                    cout <<  datbop[i].bopname << endl;
            }
            break;
        case 'q': exit = 1; break;
        }
        if (exit == 1)
        {
            exit = 0;
            break;
        }
        cout << "Next choice: ";

    }
    cout << "Bye!\n";
}
        //6.5
void P6_5(void)
{
    int tvarp;
    cout << "Enter your tvarps: ";
    while( (cin>>tvarp) && tvarp>=0)
    {
        if(tvarp <= 5000)
            cout << "No tax!\n";
        else if(tvarp>5000 && tvarp <=15000)
            cout << "Your tax is " << (tvarp-5000)*0.1 << endl;
        else if(tvarp>15000 && tvarp <=35000)
            cout << "Your tax is " << 1000+(tvarp-15000)*0.15 << endl;
        else if(tvarp>35000)
            cout << "Your tax is " << 4000+(tvarp-35000)*0.2 << endl;
        cout << "Please enter your tvarps (enter a negative value or none value to end): ";
    }
    cout << "Bye!";
}
struct donate
{
    string name;
    double money;
};
        //6.6
void P6_6(void)
{
    donate *dolist = new donate [5];
    int i = 0, gra = 0;
    while (i<5 && cin)
    {
        cout << "Enter your name: ";
        getline(cin, (dolist+i)->name);
        cout << "Enter your money: ";
        cin >> (dolist+i)->money;
        cin.get();
        i++;
    }
    cout << "Grand Patrons:\n";
    for (i=0; i<5; ++i)
    {
        if(dolist[i].money>=10000)
        {
            cout << dolist[i].name << ": " << dolist[i].money << endl;
            gra++;
        }
    }
    if (gra == 0)
        cout << "none!\n";
    gra = 0;
    cout << "Patrons: \n";
    for (i=0; i<5; ++i)
        if(dolist[i].money<10000)
        {
            cout << dolist[i].name << ": " << dolist[i].money << endl;
            gra++;
        }

    if (gra == 0)
        cout << "none!\n";
    return;
}
        //6.7
void P6_7()
{
    string word;
    int vowels = 0;
    int consonants = 0;
    int others = 0;
    while(cin >> word)
    {
        if(word.length() == 1 && word[0]=='q')
            break;
        if( isalpha(word[0]) )
        {
            if (word[0]=='a'||word[0]=='A'||
                word[0]=='e'||word[0]=='E'||
                word[0]=='i'||word[0]=='I'||
                word[0]=='o'||word[0]=='O'||
                word[0]=='u'||word[0]=='U')
                vowels++;
            else
                consonants++;
        }
        else
            others++;
    }
    cout << vowels << " words beginning with vowels\n";
    cout << consonants << " words beginning with consonants\n";
    cout << others << " others";
    return;
}
    //6.8
void P6_8()
{
    ifstream fin;
    fin.open("practice6.8.txt");
    if (!fin.is_open())
    {
        cout << "Can not open the file.\n";
        cout << "Program terminated\n";
        exit(EXIT_FAILURE);
    }
    char ch;
    int counter = 0;
    while(fin.get(ch))
    {
        counter++;
        fin.get(ch);
    }
    fin.close();
    cout << counter << " characters inputed.";
    return;
}
        //6.9
void P6_9(void)
{
    fstream fin;
    fin.open("practice6.9.txt");
    int donate_size;
    fin >> donate_size;
    fin.get();
    donate *dolist = new donate [donate_size];
    int i = 0, gra = 0;
    while (i<donate_size && fin)
    {
        getline(fin, (dolist+i)->name);
        fin >> (dolist+i)->money;
        fin.get();
        i++;
    }
    cout << "Grand Patrons:\n";
    for (i=0; i<donate_size; ++i)
    {
        if(dolist[i].money>=10000)
        {
            cout << dolist[i].name << ": " << dolist[i].money << endl;
            gra++;
        }
    }
    if (gra == 0)
        cout << "none!\n";
    gra = 0;
    cout << "Patrons: \n";
    for (i=0; i<donate_size; ++i)
        if(dolist[i].money<10000)
        {
            cout << dolist[i].name << ": " << dolist[i].money << endl;
            gra++;
        }
    if (gra == 0)
        cout << "none!\n";
    return;
}


int main()
{

    P6_9();
    return 0;
}