Question

我得到了：

Error   1   error C2059: syntax error : 'type'  c:\users\user\documents\visual studio 2010\projects\ex4\q4\tree.h   40  1   Q4
Error   2   error C2059: syntax error : 'type'  c:\users\user\documents\visual studio 2010\projects\ex4\q4\tree.c   174 1   Q4

max()位于tree.c的底部。

这是tree.h：

#ifndef __TREE_H
#define __TREE_H

/***** Type definitions *****/

typedef struct TreeNode{ 
    int data; 
    struct TreeNode* left; 
    struct TreeNode* right; 
} TreeNode; 
typedef struct tree{ 
    TreeNode* root; 
} Tree;

/****** Prototypes *****/

/* Testing trees */
Tree testTreeCase1();
Tree testTreeCase2();
Tree testTreeCase3();
Tree testTreeCase4();
Tree testTreeCase5();

/* This function creates a new node */
TreeNode* createNewTreeNode(int data, TreeNode *left, TreeNode *right);
/* This function deallocates a given tree */
void freeTree(Tree *tr);
void freeTreeHelper(TreeNode *root);
/* This function returns the number of nodes of a given tree */
int numNodes(Tree *tr);
int numNodesHelper(TreeNode *root);

/* This function returns the sum of all of the nodes data of a given tree */
int sumNodes(Tree *tr);
int sumNodesHelper(TreeNode *root);

int height(Tree *tr);
int heightHelper(TreeNode *root);

int max(int a, int b);
#endif

和这里的tree.c：

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

/* This function creates a new node */
TreeNode* createNewTreeNode(int data, TreeNode *left, TreeNode *right)
{
    TreeNode *res;
    res = (TreeNode*)malloc(sizeof(TreeNode));
    res->data = data;
    res->left = left;
    res->right = right;
    return res;
}
/* Shell function for numNodes() */
int numNodes(Tree *tr)
{
    return numNodesHelper(tr->root);
}
/* This function returns the number of nodes of a given tree's root node */
int numNodesHelper(TreeNode *root)
{
    int numNodesLeft, numNodesRight;

    if (root == NULL)
        return 0;

    else
    {
        numNodesLeft = numNodesHelper(root->left);
        numNodesRight = numNodesHelper(root->right);
        return numNodesLeft + numNodesRight + 1;
    }
}
/* Shell function for sumNodes() */
int sumNodes(Tree *tr)
{
    return sumNodesHelper(tr->root);
}
/* This function returns the sum of all of the nodes data of a given tree's root node */
int sumNodesHelper(TreeNode *root)
{
    int sumNodesLeft, sumNodesRight;

    if (root == NULL)
        return 0;

    else
    {
        sumNodesLeft = sumNodesHelper(root->left);
        sumNodesRight = sumNodesHelper(root->right);
        return sumNodesLeft + sumNodesRight + root->data;
    }
}
/* Shell function for freeTree() */
void freeTree(Tree *tr)
{
    freeTreeHelper(tr->root);
    tr->root = NULL;
}
/* This function deallocates a given tree's root node */
void freeTreeHelper(TreeNode *root)
{
    if (root == NULL)
        return;

    else if (root->left == NULL && root->right == NULL)
        free(root);

    else
    {
        freeTreeHelper(root->right);
        freeTreeHelper(root->left);
        free(root);
    }
}
/* Shell function for heightHelper() */
int height (Tree *tr) 
{
    return heightHelper(tr->root);
}
/* This function returns the height of a given tree's root node */
int heightHelper(TreeNode *root)
{
    int heightLeft, heightRight;

    if (root == NULL) // case empty tree
        return -1;

    else if (root->left == NULL && root->right == NULL)
        return 0;

    else if (root->left == NULL)
        return 1 + heightHelper(root->right);

    else if (root->right == NULL)
        return 1+ heightHelper(root->left);

    else
    {
        heightLeft = heightHelper(root->left);
        heightRight = heightHelper(root->right);
        return 1 + (heightLeft>heightRight?heightLeft:heightRight);
    }
}

// Checking trees according to special cases 
/* Case 1: Empty tree */
Tree testTreeCase1()
{

    Tree resTree;
    resTree.root = NULL;
    return resTree;

}
/* Case 2: Only root node */
Tree testTreeCase2()
{
    Tree resTree;
    TreeNode  *root;

    root = createNewTreeNode(1, NULL, NULL);
    resTree.root = root;

    return resTree;
}
/* Case 3: Only right sub-tree exists */
Tree testTreeCase3()
{
    Tree resTree;
    TreeNode  *root, *l1_r, *l2_rr, *l2_rl;

    l2_rl = createNewTreeNode(4, NULL, NULL);
    l2_rr = createNewTreeNode(3, NULL, NULL);
    l1_r = createNewTreeNode(2, l2_rl, l2_rr);
    root = createNewTreeNode(1, NULL, l1_r);
    resTree.root = root;

    return resTree;
}
/* Case 4: Only left sub-tree exists */
Tree testTreeCase4()
{
    Tree resTree;
    TreeNode  *root, *l1_l, *l2_lr, *l2_ll;

    l2_ll = createNewTreeNode(4, NULL, NULL);
    l2_lr = createNewTreeNode(3, NULL, NULL);
    l1_l = createNewTreeNode(2, l2_ll, l2_lr);
    root = createNewTreeNode(1, l1_l, NULL);
    resTree.root = root;

    return resTree;
}
/* Case 5: Both left and right sub-trees exists */
Tree testTreeCase5()
{
    Tree resTree;
    TreeNode  *root, *l1_r, *l1_l, *l2_lr, *l2_ll, *l2_rr, *l2_rl;

    l2_ll = createNewTreeNode(7, NULL, NULL);
    l2_lr = createNewTreeNode(6, NULL, NULL);
    l2_rl = createNewTreeNode(5, NULL, NULL);
    l2_rr = createNewTreeNode(4, NULL, NULL);
    l1_l = createNewTreeNode(2, l2_ll, l2_lr);
    l1_r = createNewTreeNode(3, l2_rl, l2_rr);
    root = createNewTreeNode(1, l1_l, l1_r);
    resTree.root = root;

    return resTree;
}

int max(int a, int b)
{
    return a>b ? a:b;
}

Answer 1

问题是max可能在您使用的另一个库中保留。在使用C语言处理大型应用程序时，这是一个常见问题。解决方案是将您的函数从max重命名为my_max（或删除已保留max的库。）

错误C2059定义max（）函数时

1 个答案: