Question

我有一个部分工作的选择排序算法，我用它来按年龄对类对象的数组进行排序，当它执行此操作时，它正确地排序了一些内容但未能对第一个元素进行排序。还有一种方法可以使用类的赋值运算符来使它更容易。

感谢

下面是我的完整代码：

#include <iostream>
#include <string>
#include <math.h>

using namespace std;

void storeinfo() ;
void showinfo() ;
void menu() ;
void deleteinfo() ;
void displayallinfo() ;
void selectionSort() ;
int linsearch(string val) ;


class user 
{
    string firstname, lastname, currentteam, position, status ;
    int age ;
public:
    user() {};
    user(string fname, string lname, string cteam, string pos, string stat, int age) 
    {
        setFirstName(fname);
        setLastName(lname);
        setCurrentTeam(cteam);
        setPosition(pos);
        setStatus(stat);
        setAge(age);
    } ;



    user& operator = (const user& source)
    {
        firstname = source.firstname;
        lastname = source.lastname ;
        currentteam = source.currentteam ;
        position = source.position ;
        status = source.status ;
        age = source.age ;
    }


    void setFirstName(string fname)
        {firstname = fname;}
    void setLastName(string lname)
        {lastname = lname;}
    void setCurrentTeam(string cteam)
        {currentteam = cteam;}
    void setPosition(string pos)
        {position = pos;}
    void setStatus(string stat)
        {status = stat;}
    void setAge(int _age)
        {age = _age;}

    string getFirstName()
        {return firstname ;}
    string getLastName()
        {return lastname ;}
    string getCurrentTeam()
        {return currentteam ;}
    string getPosition()
        {return position ;}
    string getStatus()
        {return status ;}
    int getAge()
        {return age ;}
};

user player[20] ;
int arrlength = 3 ;

int main()
{
    menu() ;

    cin.get() ;
    return 0 ;
}

void storeinfo()
{
    string firstname ;
    string lastname ;
    string currentteam ;
    string position;
    string status ;
    int age ;

    for (int i=0; i < 3; i++)
    {
        cout << "\n\n Enter First Name : " ; 
        cin >> firstname ;
        player[i].setFirstName(firstname) ;
        cout << "Enter Last Name : " ; 
        cin >> lastname ;
        player[i].setLastName(lastname) ;
        cout << "Enter Player's Age : " ; 
        cin >> age;
        player[i].setAge(age) ;
        cout << "Enter Current Team : " ; 
        cin >> currentteam ;
        player[i].setCurrentTeam(currentteam) ;
        cout << "Enter Position : " ; 
        cin >> position ;
        player[i].setPosition(position) ;
        cout << "Enter Status : " ; 
        cin >> status ;
        player[i].setStatus(status) ;

        cout << "\n\n\n" ;
    }

    /*cout << string(50, '\n');*/

    menu() ;

}

void showinfo()
{
    string search;
    int found ;


    cout << "Please Enter The Player's Last Name : " ;
    cin >> search ;

    found=linsearch(search);

    if (found==-1)
    {
        cout << "\n There is no player called " << search ;
    }
    else
    {
        cout << "\n First Name : " << player[found].getFirstName() << "\n" << "Last Name : " << player[found].getLastName() <<
            "\n" << "Age : " << player[found].getAge() << "\n" << "Current Team : " << player[found].getCurrentTeam() << 
            "\n" << "Position : " << player[found].getPosition() << "\n" << "Status :  " << player[found].getStatus()  << "\n\n";
    }

    cin.get() ;

    menu() ;

}

void deleteinfo()
{
    int arrlength = 3 ;
    string search ;
    int found ;

    cout << "\n Delete A Player's Information \n\n" ;
    cout << "Please Enter The Player's Last Name : " ;
    cin >> search ;

        found=linsearch(search);

    if (found==-1)
    {
        cout << "\n There is no player called " << search ;
    }
    else
    {
        for (int i=found + 1; i < arrlength; ++i)
        {
            player[i-1].setFirstName(player[i].getFirstName()) ;
            player[i-1].setLastName(player[i].getLastName()) ;
            player[i-1].setAge(player[i].getAge()) ;
            player[i-1].setCurrentTeam(player[i].getCurrentTeam()) ;
            player[i-1].setPosition(player[i].getPosition()) ;
            player[i-1].setStatus(player[i].getStatus()) ;
        }

        --arrlength ;

        cout << "\n Player has been deleted." ;

        player[arrlength].setAge(0) ;
        player[arrlength].setCurrentTeam("") ;
        player[arrlength].setFirstName("") ;
        player[arrlength].setLastName("") ;
        player[arrlength].setPosition("") ;
        player[arrlength].setStatus("");
    }

    cin.get() ;

    menu() ;
}

void displayallinfo()
{

    selectionSort();

    for (int i=0; i < 3; i++)
    {
        cout << "\n First Name : " << player[i].getFirstName() << "\n" << "Last Name : " << player[i].getLastName() <<
            "\n" << "Age : " << player[i].getAge() << "\n" << "Current Team : " << player[i].getCurrentTeam() << 
            "\n" << "Position : " << player[i].getPosition() << "\n" << "Status :  " << player[i].getStatus()  << "\n\n";
    }

    cin.get() ;

    menu() ;
}

void menu()
{
    cout << "\n\n MENU" << "\n" ;
    cout << "\n A. Store Player Information" ;
    cout << "\n B. Show Player Informaton" ;
    cout << "\n C. Delete Player Information" ;
    cout << "\n D. Display All Players Sorted By Age";
    cout << "\n Z. Exit \n\n" ;

    string x =  "";
    cin >> x ;

    if (x=="a" | x=="A")
    { 
        storeinfo() ;
    }
    else if (x=="b" | x=="B")
    {
        showinfo() ;
    }
    else if (x=="c" | x=="C")
    {
        deleteinfo() ;
    }
    else if (x=="d" | x=="D")
    {
        displayallinfo() ;
    }
    else if (x=="z" | x=="Z")
    {
        exit(0) ;
    }
    else
    {
        cout << "Invalid Choice" ;
        menu() ;
    }
}

int linsearch(string val)
{
    for (int j=0; j <= 3; j++)
    {
        if  (player[j].getLastName()==val)
         return j ;         
    }
        return -1 ;
}

void selectionSort()
{
    int i, minIndex, minValue;
    for (i = 0; i < (arrlength - 1); i++)
    {
        minIndex = i ;
        minValue = player[i].getAge() ;
        for (int index = i + 1; index < arrlength; index++)
        {
            if (player[index].getAge() < minValue)
            {
                minValue = player[index].getAge();
                minIndex = index;

            }
        }

        player[minIndex].setAge(player[i].getAge());
        player[i].getAge() == minValue;

    }



}

Answer 1

您的“用户”类很简单，因此它不需要重载赋值运算符，因为它的所有成员都是普通旧数据类型或者已经拥有自己的赋值运算符（例如字符串）。我建议从这个类中删除operator =方法，这样你就不会在添加新成员时维护operator =方法。如果需要，C ++将自动为您的类生成赋值运算符（执行成员赋值）。当你有成员指针时，你真的只需要一个重载的赋值运算符，但我离题了。

您的选择排序功能实际上并不是排序玩家。它只是为每个玩家重新安排“年龄”值。我认为这是你想要实际“排序”“玩家”阵列的目的。（请注意，这比“C ++”更“C”，但与我一起）。

void SimpleButSlowSort()
{
    bool fSorted = false;

    if (arrLength <= 1)
    {
       return;
    }

    while (fSorted)
    {
        fSorted = true;
        for (int index = 0; index < arrLength-1; index++)
        {
            if (player[index].getAge() > player[index+1].getAge())
            {
                user temp;
                temp = player[index];
                player[index] = player[index+1];
                player[index+1] = temp;
                fSorted = false;   
            }   
        }
    }
}

但是如果你想要一种更加C ++标准的排序方式，你可以使用标准库。但这需要玩家处于可以迭代的类型中。实施例

bool MyPlayerCompare(user& u1, user& u2) { return (u1.getAge() < u2.getAge()); }
std::vector<user> players;
void FasterSort()
{
    std::sort(players.begin(), players.end(), MyPlayerCompare);

}

选择排序类对象的数组

1 个答案: