c - 二叉搜索树的删除函数出错

Question

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


typedef struct treenode
{
   int data;
   struct treenode *left;
   struct treenode *right;
}tnode;

tnode * insert(tnode *node,int data)
{ 
    if(node==NULL)
    {
       node=(tnode *)malloc(sizeof(tnode));
       node->data=data;
       node->left=node->right=NULL;
       return node;
    }

if(data>node->data)
{
    node->right=insert(node->right,data);
}
else if(data<node->data)
{
    node->left=insert(node->left,data);
}

return node;
 }


 tnode * find(tnode *node,int data)

  {
  if(node==NULL)
      return NULL;


if(node->data<data)
return find(node->right,data);

else if(node->data>data)
return find(node->left,data);

else
return node;
  }

 tnode* maximal(tnode *node)

{

 if(node==NULL)
    {
       return NULL;
    }

    if(node->right) 
      return maximal(node->right);

    else 
      return node;

}


 tnode* minimal(tnode *node)

 {
    if(node==NULL)
    {
       return NULL;
    }

    if(node->left) 
      return minimal(node->left);

    else 
      return node;
}

 tnode * delete(tnode *node,int data)

  {
       tnode *temp;

       if(node==NULL)
       {
              printf("Element Not Found");
       }

       else if(data < node->data)

       {
              node->left = delete(node->left, data);
       }

       else if(data > node->data)

      {
              node->right = delete(node->right, data);
      }

      else
      {
            /* Now We can delete this node and replace with either minimum element 
               in the right sub tree or maximum element in the left subtree */
            if(node->right && node->left)
            {
                    /* Here we will replace with minimum element in the right sub tree */
                    temp = minimal(node->right);
                    node -> data = temp->data; 
                    /* As we replaced it with some other node, we have to delete that node */
                    node -> right = delete(node->right,temp->data);
            }
            else
            {
                    /* If there is only one or zero children then we can directly 
                       remove it from the tree and connect its parent to its child */
                    temp = node;
                    if(node->left == NULL)
                            node = node->right;
                    else if(node->right == NULL)
                            node = node->left;
                    free(temp); /* temp is longer required */ 
            }
    }
    return node;

   }





   int main()

   {
      tnode *root=NULL,*temp;
      //int maximum,minimum;
      int op,n;
      do

         {
    printf("\n1.insertion");
    printf("\n2.deletion");
    printf("\n3.preorder");
    printf("\n4.inorder");
    printf("\n5.postorder");
    printf("\n6.minimal node");
    printf("\n7.maximum node");
    printf("\n8.find node");
    printf("\n9.quit");
    printf("\nenter your option:");
    scanf("%d",&op);

    switch(op)
    {
        case 1:
        printf("enter the element to be inserted:");
        scanf("%d",&n);
        root=insert(root,n);
        break;

        case 2:
        printf("enter the element to be deleted:");
        scanf("%d",&n);
        root=delete(root,n);
        break;

        case 6:
        temp=minimal(root);
        if(temp==NULL)
        printf("no elements in the tree");
        else
        printf("the minimum element found is:%d",temp->data);
        break;

        case 7:
        temp=maximal(root);
        if(temp==NULL)
        printf("no elements in the tree");
        else
        printf("the maximal element found is:%d",temp->data);
        break;

        case 8:
        printf("enter the element to be found:");
        scanf("%d",&n);
        temp=find(root,n);
        if(temp == NULL)
        printf("element not found");
        else
        printf("element found");
        break;

        default :
        exit(0);
    }
}while(op<9);

    return 0;

    }

*当我编译时，很多错误向我袭来，所有错误都与删除函数以及如何释放指针有关(两个错误与释放指针有关)。我在widows平台上使用gcc来执行程序。 *

错误如下:g++.exe -x c++ -c C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C -o C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY ~2.o -Wall -f 允许C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:97:“删除”之前解析错误

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:120: `->' 之前有语法错误

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:122:`->' 之前有语法错误

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:133:在此范围内未声明“temp”

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:133:警告:ANSI C++ 禁止声明无类型的“free”

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:133:“int free”重新声明为不同类型的符号

...\lib\gcc-lib\i386-mingw32\2.95.2........\include\stdlib.h:271: 先前声明 `void free(void *)'

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:134:“}”之前解析错误

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:在函数 `int main()' 中:

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:174:警告:逗号表达式的左侧操作数无效

C:\Users\HARSHA\DOCUME~1\GCCPRO~1\ps2\BINARY~2.C:174:类型int'参数给出删除'，预期指针

失败

Answer 1

g++ 编译 c++ 而不是 c 代码。 delete 是 C++ 中的运算符，因此不能用于函数名称。例如，尝试将函数删除的名称更改为“删除”(大写“D”)。