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我有一个部分有效的选择排序算法，我正在使用它按年龄对类对象数组进行排序，当它这样做时，它会正确排序一些内容，但无法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这更容易一些。

谢谢

以下是我的完整代码：

#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;

    }



}
4

1 回答 1

1

您的“用户”类非常简单，因此它不需要重载的赋值运算符，因为它的所有成员都是普通的旧数据类型或已经有自己的赋值运算符（例如字符串）。我建议从此类中删除 operator= 方法，这样您就无需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一个赋值运算符（按成员赋值）。当你有指针成员时，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对玩家进行排序。它只是重新排列每个玩家的“年龄”值。我认为这就是您想要对“玩家”数组进行实际“排序”的方法。（请注意，这更像是“C”而不是“C++”，但请耐心等待）。

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;   
            }   
        }
    }
}

但是如果你想要一个更 C++ 标准的排序方式，你可以使用标准库。但这要求玩家处于可以迭代的类型。例子

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

}
于 2013-01-24T02:48:59.520 回答