03-树1 树的同构 （C语言链表实现）

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdbool.h>

 typedef char ElemType;

 typedef struct BinTree
 {
     ElemType data;
     struct BinTree *left;
     struct BinTree *right;
 }BinTree;

 bool TreeCmp(BinTree * a, BinTree * b); //判断a树与b树是否同构
 BinTree * BinTree_new(int n);

 int main()
 {
     int n;
     scanf("%d", &n);
     BinTree * a = BinTree_new(n);
     scanf("%d", &n);
     BinTree * b = BinTree_new(n);

     bool flag = TreeCmp(a, b);
     if (flag)
         printf("Yes");
     else
         printf("No");

     ;
 }

 BinTree * BinTree_new(int n)
 {
     )
     {
         return  NULL;
     }
     else
     {
         int i, li, ri;
         ElemType c, lc, rc;
         BinTree * T = (BinTree *)malloc(n * sizeof(BinTree));
         bool *head = (bool *)malloc(n * sizeof(bool));

         memset(head, true ,sizeof(head));

         ; i < n ; ++i )
         {
             scanf(" %c %c %c", &c, &lc, &rc);

             li = lc-';
             ri = rc-';

             T[i].data = c;

             if (lc != '-')
             {
                 T[i].left = &T[li];
                 head[li] = false;
             }
             else
                 T[i].left = NULL;

             if (rc != '-')
             {
                 T[i].right = &T[ri];
                 head[ri] = false;
             }
             else
                 T[i].right = NULL;

         }

         //寻找树的树根（树根没有其它的结点指向它）
         ; i < n ; ++i )
             if (head[i] == true)
                 break;
         free(head);
         return &T[i];
     }
 }

 bool TreeCmp(BinTree * a, BinTree * b)
 {
     if (a == NULL && b == NULL)//两棵树都为空
         return true;

     if (a == NULL || b == NULL)//有一棵树为空
         return false;

     if (a->data != b->data)//树结点的值不相等
         return false;

     if (a->left == NULL && b->left == NULL)//两棵树的左子树都为空
         return TreeCmp(a->right, b->right);//就比较右子树

     //两棵树的左子树都不为空，且两个值相等就比较两棵树的子树
     if (a->left != NULL && b->left != NULL &&(a->left->data == b->left->data))
         return (TreeCmp(a->left,b->left)&&TreeCmp(a->right,b->right));

     //交换后再比较
     else
         return (TreeCmp(a->left,b->right)&&TreeCmp(a->right,b->left));
 }