二叉树的存储结构

#define MaxSize 100
typedef char ElemType;
struct BTNode {
    ElemType data;
    struct BTNode *lchild;
    struct BTNode *rchild;
};

创建二叉树 A(B(D(,G)),C(E,F))

void CreateBTNode(BTNode *&b,char *str) {
    BTNode *St[MaxSize],*p=NULL;
    int top=-1,k,j=0;
    char ch;
    b=NULL;
    ch=str[j];
    while(ch!='\0') {
        switch(ch) {
            case'(':
            top++;
            St[top]=p;
            k=1;
            break;
            case')':
            top--;
            break;
            case',':
            k=2;
            break;
            default:
            p=(BTNode *)malloc(sizeof(BTNode));
            p->data=ch;
            p->lchild=p->rchild=NULL;
            if(b==NULL)b=p;
            else {
                switch(k) {
                    case 1:
                    St[top]->lchild=p;
                    break;
                    case 2:
                    St[top]->rchild=p;
                    break;
                }
            }
        }
        ch=str[++j];
    }
}

查找节点

BTNode *FindNode(BTNode *b,ElemType x) {
    BTNode *p;
    if(b==NULL)
        return NULL;
    else if(b->data==x)
        return b;
    else {
        p=FindNode(b->lchild,x);
        if(p!=NULL)
            return p;
        else
            return FindNode(b->rchild,x);
    }
}

求高度

int BTNodeDepth(BTNode *b) {
    int lchilddep,rchilddep;
    if(b==NULL) return 0;
    else {
        lchilddep=BTNodeDepth(b->lchild);
        rchilddep=BTNodeDepth(b->rchild);
        return (lchilddep>rchilddep?lchilddep+1:rchilddep+1);
    }
}

打印二叉树 A(B(D(,G)),C(E,F))

void DispBTNode(BTNode *b) {
    if(b!=NULL) {
        cout<<b->data;
        if(b->lchild!=NULL || b->rchild!=NULL) {
            cout<<'(';
            DispBTNode(b->lchild);
            if(b->rchild!=NULL)
                cout<<',';
            DispBTNode(b->rchild);
            cout<<')';
        }
    }
}