树的邻接表求结点到结点的指定路径

问题：
从文本文件中提取出树的邻接表，求指定结点到指定结点的路径。
需求：
我已经完成从文本文件中提取出树的邻接表，但是不知道指定结点到指定结点的如何求解。
请求代码！(堆栈实现)
比如b2到g3无路径，a1到g3的路径为a1-》d2-》g3
以下是文本文件的内容：

以下是我目前已经完成的代码:

#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#define MAXSIZE 3
#define MAXNODESIZE 10

//ADT
typedef struct Branch
{
    int index;
    struct Branch* next;
}branch;

typedef struct Tnode
{
    char data[MAXSIZE];
    branch* first;
}tnode;

void create(tnode tree[], char str[], int cnt)  //创建邻接表
{
    int j = 0, t = 0;
    for (int i = 0; i < cnt; i++)
    {
        j = 0;
        while (str[t] != '/')  //遇到/就开始找换行符\n，并跳转到下一行，录入下一行头节点
        {
            tree[i].data[j] = str[t];
            j++;
            t++;
        }
        tree[i].data[j] = '\0';  //为tree[i].data加入终止符
        tree[i].first = NULL;
        while (str[t] != '\n' && str[t] != EOF)  //跳转至下一行，准备录下一行的头节点
            t++;
        t++;
    }
    //头节点初始化完成，接下来将子节点连接到头结点
    t = 0;
    int size = strlen(str);
    for (int i = 0; i < cnt && t < size; i++)  //这里需要做两个限制：1.遍历字符串的指针t不能超过字符串长度 2.头结点个数有限制
    {
        while (t < size && str[t] != '/')  //先跳过头节点
            t++;
        t++;
        while (t < size && str[t] != '\n' && str[t] != '\0') // 这里是bug1: t是数字， 也要可能是空了
        {
            j = 0;
            char string[MAXSIZE];
            while (t < size && str[t] != '/' && str[t] != '\n')//将字符串截取出来 bug2:不能处理换行符
            {
                string[j] = str[t];
                j++;
                t++;
            }
            string[j] = '\0';  //为该截取出来的字符串添加终止符
            int target = -1;
            for (int n = 0; n < cnt; n++)
            {
                if (!strcmp(tree[n].data, string)) {
                    target = n;
                    break;
                }
            }
            branch* p = tree[i].first;
            //bug3:插入方式不正确，应该后插入
            if (p == NULL) //如果是第一次将子节点插入头结点，应该特殊处理，这里用尾插法
            {
                p = (branch*)malloc(sizeof(branch));
                p->index = target;
                p->next = NULL;
                tree[i].first = p;
            }
            else
            {
                while (p->next != NULL)  //用p定位到最后一个结点
                {
                    p = p->next;
                }
                p->next = (branch*)malloc(sizeof(branch));  //插入新的结点
                p->next->index = target;
                p->next->next = NULL;
            }
            if (t >= size || str[t] == '\n')
                break;
            t++;  //使t指向下一个单词开头 
        }
        //此时t指向\n
        t++;  //将t指向下一行第一个字符
    }
}
void FillInText(char str[], FILE* fp)  //将文件中内容传入str中
{
    char ch;
    int length = 0;
    ch = fgetc(fp);
    while (ch != EOF)
    {
        str[length] = ch;
        ch = fgetc(fp);
        length++;
    }
    str[length] = '\0';
}

int getCount(char str[])  //获取邻接表头节点个数
{
    int cnt = 0;
    for (int i = 0; i < strlen(str); i++)
    {
        if (str[i] == '\n')
            cnt++;
    }
    return cnt + 1;
}

int main()
{
    FILE* fp;
    tnode tree[MAXNODESIZE];
    for (int i = 0; i < MAXNODESIZE; i++)  //对头节点全部赋\0
    {
        for (int t = 0; t < MAXSIZE; t++)
        {
            tree[i].data[t] = '\0';
        }
    }
    char str[100];
    fp = fopen("Tree.txt", "r");
    if (fp == NULL)
    {
        printf("文件打开失败\n");
        exit(0);
    }
    FillInText(str, fp);
    fclose(fp);
    printf("");
    puts(str);
    create(tree, str, getCount(str));
    return 0;
}

#define _CRT_SECURE_NO_WARNINGS
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#define MAXSIZE 3
#define MAXNODESIZE 10

//ADT
typedef struct Branch
{
    int index;
    struct Branch* next;
}branch;

typedef struct Tnode
{
    char data[MAXSIZE];
    branch* first;
}tnode;

void create(tnode tree[], char str[], int cnt)  //创建邻接表
{
    int j = 0, t = 0;
    for (int i = 0; i < cnt; i++)
    {
        j = 0;
        while (str[t] != '/')  //遇到/就开始找换行符\n，并跳转到下一行，录入下一行头节点
        {
            tree[i].data[j] = str[t];
            j++;
            t++;
        }
        tree[i].data[j] = '\0';  //为tree[i].data加入终止符
        tree[i].first = NULL;
        while (str[t] != '\n' && str[t] != EOF)  //跳转至下一行，准备录下一行的头节点
            t++;
        t++;
    }
    //头节点初始化完成，接下来将子节点连接到头结点
    t = 0;
    int size = strlen(str);
    for (int i = 0; i < cnt && t < size; i++)  //这里需要做两个限制：1.遍历字符串的指针t不能超过字符串长度 2.头结点个数有限制
    {
        while (t < size && str[t] != '/')  //先跳过头节点
            t++;
        t++;
        while (t < size && str[t] != '\n' && str[t] != '\0') // 这里是bug1: t是数字， 也要可能是空了
        {
            j = 0;
            char string[MAXSIZE];
            while (t < size && str[t] != '/' && str[t] != '\n')//将字符串截取出来 bug2:不能处理换行符
            {
                string[j] = str[t];
                j++;
                t++;
            }
            string[j] = '\0';  //为该截取出来的字符串添加终止符
            int target = -1;
            for (int n = 0; n < cnt; n++)
            {
                if (!strcmp(tree[n].data, string)) {
                    target = n;
                    break;
                }
            }
            branch* p = tree[i].first;
            //bug3:插入方式不正确，应该后插入
            if (p == NULL) //如果是第一次将子节点插入头结点，应该特殊处理，这里用尾插法
            {
                p = (branch*)malloc(sizeof(branch));
                p->index = target;
                p->next = NULL;
                tree[i].first = p;
            }
            else
            {
                while (p->next != NULL)  //用p定位到最后一个结点
                {
                    p = p->next;
                }
                p->next = (branch*)malloc(sizeof(branch));  //插入新的结点
                p->next->index = target;
                p->next->next = NULL;
            }
            if (t >= size || str[t] == '\n')
                break;
            t++;  //使t指向下一个单词开头 
        }
        //此时t指向\n
        t++;  //将t指向下一行第一个字符
    }
}
void FillInText(char str[], FILE* fp)  //将文件中内容传入str中
{
    char ch;
    int length = 0;
    ch = fgetc(fp);
    while (ch != EOF)
    {
        str[length] = ch;
        ch = fgetc(fp);
        length++;
    }
    str[length] = '\0';
}

int getCount(char str[])  //获取邻接表头节点个数
{
    int cnt = 0;
    for (int i = 0; i < strlen(str); i++)
    {
        if (str[i] == '\n')
            cnt++;
    }
    return cnt + 1;
}

char* getPath(tnode tree[], int cnt, const char*p1 , const char*p2) {
     
    int s1=-1, s2=-1;
    char result[2048] = "\0";
    for (int i = 0; i < cnt; i++) {
        if (!strcmp(tree[i].data, p1)) {
            s1 = i;
        }
        if (!strcmp(tree[i].data, p2)) {
            s2 = i;
        }
    }
    if (s1 == -1 || s2 == -1) {
        printf("字符串匹配异常");
        memcpy(result, "NULL", 5);
        return result;
    }
    int path[MAXNODESIZE];
    memset(path, -1, sizeof(int) * MAXNODESIZE);

    int visited[MAXNODESIZE];
    memset(visited, 0, sizeof(int) * MAXNODESIZE);

    //深度优先:用栈
    int stack[MAXNODESIZE];
    int top = -1;
    stack[++top] = s1;
    int pathIndex = -1; 
    visited[s1] = 1;
    //栈非空
    while (top >= 0) {
        //出栈
        int pre = stack[top--];
        path[++pathIndex] = pre;
        if (pre == s2) { break; }
        for (branch* w = tree[pre].first; w != NULL; w = w->next) {
            if (!visited[w->index]) {
                //没有访问过，入栈
                stack[++top] = w->index; 
            }
        }
    }
  
    if (path[pathIndex] != s2) {
        memcpy(result, "NULL", 5);
        return result;
    }
    else {
        strcat(result, tree[path[0]].data);
        for (int i = 1; i <= pathIndex; i++) {
            strcat(result, "->");
            strcat(result, tree[path[i]].data);
        }  
        return result;
    }
}


int main()
{
    FILE* fp;
    tnode tree[MAXNODESIZE];
    for (int i = 0; i < MAXNODESIZE; i++)  //对头节点全部赋\0
    {
        for (int t = 0; t < MAXSIZE; t++)
        {
            tree[i].data[t] = '\0';
        }
    }
    char str[100];
    fp = fopen("C:\\Users\\Lenovo\\Desktop\\Tree.txt", "r");
    if (fp == NULL)
    {
        printf("文件打开失败\n");
        exit(0);
    }
    FillInText(str, fp);
    fclose(fp);
  
    puts(str);
    create(tree, str, getCount(str));
    int cnt = getCount(str);
 
    char*path = getPath(tree,cnt, "b2", "g3");
    printf("%s", path);
    return 0;
}