纪念逝去的岁月——C/C++排序二叉树

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

typedef struct _Node
{
    int value;
    struct _Node * pLeft;
    struct _Node * pRight;
} Node;

Node * getNewNode(int iValue)
{
    Node * p = (Node *)malloc(sizeof(Node));
    if(NULL != p)
    {
        p->value = iValue;
    }

    return p;
}

void deleteNode(Node * p)
{
    if(NULL != p)
    {
        free(p);
    }
}

int addElm(Node * p, int value)
{
    Node * pX = p;
    while(pX)
    {
        if(value < pX->value)
        {
            if(NULL == pX->pLeft)
            {
                pX->pLeft = getNewNode(value);
                printf("add [%2d] to left  of [%2d]\n", value, pX->value);
                break;
            }
            else
            {
                pX = pX->pLeft;
            }
        }
        else
        {
            if(NULL == pX->pRight)
            {
                pX->pRight = getNewNode(value);
                printf("add [%2d] to right of [%2d]\n", value, pX->value);
                break;
            }
            else
            {
                pX = pX->pRight;
            }
        }
    }

    return 0;
}

Node * makeBinaryTree(int iList[], int iNum)
{
    Node * p = getNewNode(iList[0]);
    int i = 0;
    for(i = 1; i < iNum; i++)
    {
        addElm(p, iList[i]);
    }
    printf("\n");

    return p;
}

void destroyBinaryTree(Node * p)
{
    if(NULL == p)
    {
        return;
    }
    destroyBinaryTree(p->pLeft);
    destroyBinaryTree(p->pRight);
    free(p);
}

int preorderTraversal(Node * p)
{
    if(NULL == p)
    {
        return -1;
    }
    printf("%2d ", p->value);
    preorderTraversal(p->pLeft);
    preorderTraversal(p->pRight);
    return 0;
}

int postorderTraversal(Node * p)
{
    if(NULL == p)
    {
        return -1;
    }
    postorderTraversal(p->pLeft);
    postorderTraversal(p->pRight);
    printf("%2d ", p->value);
    return 0;
}

int inorderTraversal(Node * p)
{
    if(NULL == p)
    {
        return -1;
    }
    inorderTraversal(p->pLeft);
    printf("%2d ", p->value);
    inorderTraversal(p->pRight);
    return 0;
}

void preTrvl(Node * p)
{
    printf("pre  : ");
    preorderTraversal(p);
    printf("\n");
}

void postTrvl(Node * p)
{
    printf("post : ");
    postorderTraversal(p);
    printf("\n");
}

void inTrvl(Node * p)
{
    printf("in   : ");
    inorderTraversal(p);
    printf("\n");
}

void printList(int iList[], int iNum)
{
    for(int i = 0; i < iNum; i++)
    {
        printf("%d ", iList[i]);
    }
    printf("\n");
}

int main()
{
    int iList[15] = {8, 0, 3, 12, 11, 4, 13, 6, 10, 9, 1, 5, 14, 2, 7};
    int iNum = 15;

    printList(iList, iNum);
    Node * p = makeBinaryTree(iList, iNum);
    preTrvl(p);
    postTrvl(p);
    inTrvl(p);
    destroyBinaryTree(p);
}

 1 $ ./binaryTree 
 2 8 0 3 12 11 4 13 6 10 9 1 5 14 2 7 
 3 add [ 0] to left  of [ 8]
 4 add [ 3] to right of [ 0]
 5 add [12] to right of [ 8]
 6 add [11] to left  of [12]
 7 add [ 4] to right of [ 3]
 8 add [13] to right of [12]
 9 add [ 6] to right of [ 4]
10 add [10] to left  of [11]
11 add [ 9] to left  of [10]
12 add [ 1] to left  of [ 3]
13 add [ 5] to left  of [ 6]
14 add [14] to right of [13]
15 add [ 2] to right of [ 1]
16 add [ 7] to right of [ 6]
17 
18 pre  :  8  0  3  1  2  4  6  5  7 12 11 10  9 13 14 
19 post :  2  1  5  7  6  4  3  0  9 10 11 14 13 12  8 
20 in   :  0  1  2  3  4  5  6  7  8  9 10 11 12 13 14