二叉树先序中序后序递归遍历，层次非递归遍历

[c]代码库

#include <stdio.h>
#include <stdlib.h>
typedef char ElementType;
typedef struct TNode *Position;
typedef Position BinTree;
struct TNode{
    ElementType Data;
    BinTree Left;
    BinTree Right;
};

BinTree CreatBinTree(); /* 实现细节忽略 */
void InorderTraversal( BinTree BT )
{
    if(BT)
    {
        InorderTraversal(BT->Left);
        printf(" %c",BT->Data);
        InorderTraversal(BT->Right);
    }
}
void PreorderTraversal( BinTree BT )
{
    if(BT)
    {
        printf(" %c",BT->Data);
        PreorderTraversal(BT->Left);
        PreorderTraversal(BT->Right);
    }
}
void PostorderTraversal( BinTree BT )
{
    if(BT)
    {
        PostorderTraversal(BT->Left);
        PostorderTraversal(BT->Right);
        printf(" %c",BT->Data);
    }
}
void LevelorderTraversal( BinTree BT )
{
    if(BT)
    {
        int i,j;
        struct TNode *q[200],*p; /*q[200]用于模拟队列，存储入队的结点*/
        i=0;
        q[i]=BT;
        j=1;/*i为队首位置，j为队尾位置*/
        while(i!=j)
        {
            p=q[i];
            printf(" %c",p->Data); /*访问队首元素*/
            if(p->Left)
                q[j++]=p->Left;/*若队首元素左链域不为空，则将其入队列*/
            if(p->Right)
                q[j++]=p->Right;/*若队首元素右链域不为空，则将其入队列*/
            i++; /*将队首移到下一个位置*/
        }
    }
}
int main()
{
    BinTree BT = CreatBinTree();
    printf("Inorder:");    InorderTraversal(BT);    printf("\n");
    printf("Preorder:");   PreorderTraversal(BT);   printf("\n");
    printf("Postorder:");  PostorderTraversal(BT);  printf("\n");
    printf("Levelorder:"); LevelorderTraversal(BT); printf("\n");
    return 0;
}