1题目

求二叉树A的镜像，就是对称图，比如下面的树B是树A的镜像
比如：
              2                           2
   树A  3    5      树B        5     3
        1  4  2  3              3   2  4  1 
 

 

 

 

 

 

 

 

2 代码实现

#include <stdio.h>#define true 1
#define false 0typedef struct Node
{int value;struct Node* left;struct Node* right;
} Node;void reverse_tree(Node *head)
{if (head != NULL){Node *temp = head->left;head->left = head->right;head->right = temp;reverse_tree(head->left);reverse_tree(head->right);}
}
void reverse_tree1(Node *head)
{if (head == NULL){return;}if (head->left == NULL && head->right == NULL){return;}Node *temp = head->left;head->left = head->right;head->right = temp;//if (head->left != NULL)reverse_tree(head->left);//if (head->right != NULL)reverse_tree(head->right);
}void printf_tree(Node *head)
{if (head != NULL){printf("val is: %d\n", head->value);printf_tree(head->left);printf_tree(head->right);}
}int main()
{/*              2*           3    5            5*         1  4  2  3        2   3*       */Node head1, node1, node2, node3, node4, node5, node6;Node head2, node7, node8;head1.value = 2;node1.value = 3;node2.value = 5;node3.value = 1;node4.value = 4;node5.value = 2;node6.value = 3;head1.left = &node1;head1.right = &node2;node1.left = &node3;node1.right = &node4;node2.left = &node5;node2.right = &node6;node3.left = NULL;node3.right = NULL;node4.left = NULL;node4.right = NULL;node5.left = NULL;node5.right = NULL;node6.left = NULL;node6.right = NULL;head2.value = 5;node7.value = 2;node8.value = 3;head2.left = &node7;head2.right = &node8;node7.left = NULL;node7.right = NULL;node8.left = NULL;node8.right = NULL;printf_tree(&head1);printf("----\n");reverse_tree(&head1);printf_tree(&head1);
｝

 

 

 

 

 

 

3 运行结果

val is: 2
val is: 3
val is: 1
val is: 4
val is: 5
val is: 2
val is: 3
----
val is: 2
val is: 5
val is: 3
val is: 2
val is: 3
val is: 4
val is: 1