完全二叉树的创建

创建二叉树：输入0结束

void CreateTree(BinaryTree **pTree)
{
    //输入数值
    int nNum;
    scanf("%d",&nNum);

    if(nNum == 0)return;

    *pTree = (BinaryTree*)malloc(sizeof(BinaryTree));
    (*pTree)->nValue = nNum;
    (*pTree)->pLeft = NULL;
    (*pTree)->pRight = NULL;

    //左
    CreateTree(&((*pTree)->pLeft));
    //右
    CreateTree(&((*pTree)->pRight));
}

创建二叉树：输入#结束，需要注意的是%c读入空格和换行，所以输入的时候要一连串输入，

void  CreateTree(Tree** tmp)
{
    char num = 0;
    scanf("%c",&num);
    if(num == '#') return;
    *tmp = (Tree*)malloc(sizeof(Tree));
    (*tmp)->val = num - '0';
    (*tmp)->pleft = NULL;
    (*tmp)->pright = NULL;
    CreateTree(&((*tmp)->pleft));
    CreateTree(&((*tmp)->pright));
}

测试数据：124##5##36###     

前序输出结果为：124536

函数为前序插入，只能为前序插入

将数组元素作为前序遍历的结果建立二叉树：

根从0开始，第2*i+1个节点为它的左孩子，2*i+2为它的右孩子

Tree* Create(int* arr,int len)
{
    if(arr == NULL || len == 0) return NULL;
    Tree* tree = (Tree*)malloc(sizeof(Tree)*len);
    
    for(int i = 0; i < len; i++)
    {    
        tree[i].val = arr[i];
        if((2*i+1) < len)
            tree[i].pleft = &tree[2*i+1];
        else
            (tree[i]).pleft = NULL;
        if((2*i+2) < len)
            tree[i].pright = &tree[2*i+2];
        else
            tree[i].pright = NULL;
    }
    return tree;
}