查找 - 平衡二叉树（N）

#include<cstdio>
#include<cstdlib>
#include<cstring>
#define LH +1
#define EH 0
#define RH -1

typedef struct BiTNode{
	int data;
	int bf;	//结点的平衡因子
	struct BiTNode *lchild,*rchild; 
}BiTNode,*BiTree;

//右旋
void R_Rotate(BiTree *p){
	BiTree L;
	L = (*p)->lchild;
	(*p)->lchild = L->rchild;
	L->rchild = (*p);
	*p = L; 
} 
//左旋
void L_Rotate(BiTree *p) {
	BiTree R;
	R = (*p)->rchild;
	(*p)->rchild = R->lchild;
	R->lchild = (*p);
	*p = R;
}

//左平衡旋转处理
void LeftBalance(BiTree *T){
	BiTree L,Lr;
	L = (*T)->lchild;
	switch(L->bf){
		case LH:
			(*T)->bf = L->bf = EH;
			R_Rotate(T);
			break;
		case RH:Lr = L->rchild;
				switch(Lr->bf){
					case LH:
						(*T)->bf = RH;
						L->bf = EH;
						break;
					case EH:
						(*T)->bf = L->bf = EH;
						break;
					case RH:
						(*T)->bf = EH;
						L->bf = LH;
						break;
				}
			Lr->bf = EH;
			L_Rotate(&(*T)->lchild);
			R_Rotate(T);
	}
} 
//右平衡旋转处理
void RightBalance(BiTree *T){
	BiTree L,Ll;
	L = (*T)->rchild;
	switch(L->bf){
		case RH:
			(*T)->bf = L->bf = EH;
			L_Rotate(T);
			break;
		case LH:
			Ll = L->lchild;
			switch(Ll->bf){
				case LH:
					(*T)->bf = RH;
					L->bf = EH;
					break;
				case EH:
					(*T)->bf = L->bf = EH;
					break;
				case RH:
					(*T)->bf = RH;
					L->bf = EH;
					break;
				}
			Ll->bf = EH;
			R_Rotate(&(*T)->rchild);
			L_Rotate(T);
	}
} 

int InsertAVL(BiTree *T,int e,int *taller){
	if(!(*T)){
		*T = (BiTree)malloc(sizeof(BiTNode));
		(*T)->data = e;
		(*T)->lchild = (*T)->rchild = NULL;
		(*T)->bf = EH;
		*taller = 1;
	}else{
		if(e == (*T)->data){
			*taller = 0;
			return 0;
		}else if(e < (*T)->data){
			if(!InsertAVL(&(*T)->lchild,e,taller)) return 0;
			if(*taller){
				switch((*T)->bf){
					case LH:
						LeftBalance(T);
						*taller = 0;
						break;
					case EH:
						(*T)->bf = LH;
						*taller = 1;
						break;
					case RH:
						(*T)->bf = EH;
						*taller = 0;
						break;
				}
			}
			
		}else{
			if(!InsertAVL(&(*T)->rchild,e,taller)) return 0;
			if(*taller){
				switch((*T)->bf){
					case LH:
						(*T)->bf = EH;
						*taller = false;
						break;
					case EH:
						(*T)->bf = RH;
						*taller = 1;
						break;
					case RH:
						RightBalance(T);
						*taller = 0;
						break;
				}
			}
		}
	}
} 



void InOrderTraverse(BiTree T)  
{  
    if (T == NULL)  
    {  
        return;  
    }  
    InOrderTraverse(T->lchild);//访问左子树  
    printf("%d ",T->data);//访问根结点  
    InOrderTraverse(T->rchild);//访问右子树  
}  
int main(){
	int i;  
    int a[] = {3,2,1,4,5,6,7,10,9,8,25,13,46,26,68,98,15,12};  
    BiTree T = NULL;  
    int taller;  
    for (i=0; i<18; i++)  
    {  
        InsertAVL(&T,a[i],&taller);  
    }  
    InOrderTraverse(T);  
    printf("\n"); 
	return 0;
}