[問題] link_list指標

[LiuLiuiris (Pipi)]

開發平台(Platform): (Ex: VC++, GCC, Linux, ...) 
c++

額外使用到的函數庫(Library Used): (Ex: OpenGL, ...) 
none

問題(Question)：
ptr指標有錯誤，ptr->name或ptr->count都會出現錯誤

餵入的資料(Input)：
3
This is a test.
Count me 1 2 3 4 5.
Wow!!!! Is this question easy?
2
Good luck!
Pass.
0

預期的正確結果(Expected Output)：
S 7
T 6
I 5
E 4
O 3
A 2
H 2
N 2
U 2
W 2
C 1
M 1
Q 1
Y 1
O 2
S 2
A 1
C 1
D 1
G 1
K 1
L 1
P 1
U 1

錯誤結果(Wrong Output)：
指標有問題

程式碼(Code)：(請善用置底文網頁, 記得排版) 
#include<iostream>
#include<iomanip>
#include<cstdio>
#include<cstdlib>
#include <fstream>
using namespace std;
typedef struct list
{
    int name;
    int count;
    struct list *next;
}node;
int main()
{
    FILE *fp = fopen( "letter.txt", "r" ) ;
    if(!fp){    cout << "讀檔失敗" << endl;   }
    int data,clt,change,sum;
    char wd;
    fscanf(fp,"%d",&data);
    while(data)  //data為0終止程式
    {
        node *head = NULL;
        node *tail;
        node *new_node;
        clt = data+1;
        while(clt)  //判斷換行次數
        {
            fscanf(fp,"%c",&wd);
            change = (int)wd;
            if(change==10) clt--;  //換行字元
            else  //一般字元
            {
                if((change>64&&change<91)||(change>96&&change<123))
                {
                    if(head==NULL)  //鏈結為空
                    {
                        if((122-change)<26)  //小寫
                        {
                            new_node=(node *)malloc(sizeof(node));
                            new_node->name = change-96;
                            new_node->count = 1;
                            new_node->next = head;
                            head = new_node;
                            tail = head;
                        }
                        else  //大寫
                        {
                            new_node=(node *)malloc(sizeof(node));
                            new_node->name = change-64;
                            new_node->count = 1;
                            new_node->next = head;
                            head = new_node;
                            tail = head;
                        }
                    }
                    else  //鏈結不為空
                    {
                        node *ptr;
                        ptr = head;
                        if((122-change)<27)  //小寫
                        {
                            while((ptr!=NULL)&&(ptr->name!=change))
                            {
                                ptr = ptr->next;
                            }
                            if(ptr==NULL)
                            {
                                new_node=(node *)malloc(sizeof(node));
                                new_node->name = change-96;
                                new_node->count = 1;
                                new_node->next = tail->next;
                                tail->next = new_node;
                                tail = new_node;
                            }
                            else
                            {
                                sum = ptr->count + 1;
                                ptr->count = sum;
                            }
                        }
                        else  //大寫
                        {
                            while((ptr!=NULL)&&(ptr->name!=change))
                            {
                                ptr = ptr->next;
                            }
                            if(ptr==NULL)
                            {
                                new_node=(node *)malloc(sizeof(node));
                                new_node->name = change-64;
                                new_node->count = 1;
                                new_node->next = tail->next;
                                tail->next = new_node;
                                tail = new_node;
                            }
                            else
                            {
                                sum = ptr->count + 1;
                                ptr->count = sum;
                            }
                        }
                    }
                }
            }

        }
        /*node *temp;
        temp = head;
        for(temp;temp!=tail;temp->next)
        {
            cout << head->name;
        }*/
        fscanf(fp,"%d",&data);
    }
    system("pause");
    return 0;
}



--
※ 發信站: 批踢踢實業坊(ptt.cc) 
◆ From: 140.130.175.165
→ legnaleurc:好像強迫自己用C++又回去用C的寫法
→ legnaleurc:這個其實用陣列會比較好做
→ loveme00835:一個main...現在是在做 word count?
→ james732:一大堆的magic number看得我頭好痛啊 XD
→ legnaleurc:ctypes 是你的好朋友 :P
→ james732:同樓上，原po請盡量使用 http://ppt.cc/ll(4 來寫
→ james732:if((122-change)<27)  //小寫  <=這種程式碼讓人很頭痛呢
→ james732:也建議學習debugger如何使用，一步一步的找錯誤