Question

名
玩游戏
得分

深
5
540（头）

彼得
34个
455

Avijit
2
430

佩卡
4
310（尾巴）

对于上面的播放器列表链接列表，当Avijit得分高于Peter时，我想按升序对列表进行排序。所以它在链表中的转换操作。任何人都可以帮助我找到下面的代码中的问题来执行此操作。任何解决方案？感谢。

void Player::update_statistics(int last_game_point)
{
    player_ptr currPtr = head; // Moving pointer
    player_ptr prevPtr = NULL; // Pointer to node before *currPtr
    //player_ptr head;                //  class variable in Player class
    //player_ptr selected_player;     //  class variable in Player class
    //player_ptr previous_player;     //  class variable in Player class 

    // update selected player's data
    cout<<++(selected_player->played_games);  // increase by 1 for last game
    selected_player->total_point=(selected_player->total_point)+last_game_point;

    if ((selected_player!=head) && (previous_player->total_point < selected_player->total_point)){
        previous_player->link = selected_player->link;

        // search for appropriate position
        while (currPtr->total_point > selected_player->total_point){
            prevPtr = currPtr;
            currPtr = currPtr->link;
        }

        if (currPtr==head)
            selected_player->link=head;
            head=selected_player->link;
        }
        else {
            previous_player->link=selected_player;
            selected_player->link=currPtr;
        }
}

Answer 1

我想你想要

else {
        previous_player->link=selected_player;
        selected_player->link=currPtr;
    }

是

else {
        prevPtr->link=selected_player;
        selected_player->link=currPtr;
    }

Answer 2

如果这不是作业，而你不想在链表上学习算法的内在函数，那么你应该

使用标准库
避免在不需要指针时使用指针

那就是说，回答你的问题：

struct record {
    std::string name;
    int games_played;
    int score;
};

bool lower_score(const record& a, const record& b)
{
    return a.score < b.score;
}

// ...
std::vector<record> records = the_records();
std::sort(records.begin(), records.end(), lower_score);

我不确定你为什么要使用列表;如果你没有具体的具体原因那么你应该使用矢量。否则，std::list有一个sort()成员：

std::list<record> records = no_no_i_meant_those_records();
records.sort(lower_score);

链表中的班次操作

2 个答案: