叶子结点带权路径长度和（先序遍历法和层序遍历法）

先序遍历

//deep初值为0
int leafNodeLength(Tree r,deep)
{
    static int wpl=0;
    if(r->lchild==NULL&&r->rchild==NULL)
        wpl+=deep*r->weight;
    if(r->lchild)
        leafNodeLength(r->lchild,deep+1);
    if(r->rchild)
        leafNodeLength(r->rchild,deep+1);
    return wpl;
}

层序遍历法

int leafNodeLength(Tree r)
{
    Tree p=r;
    queue Q;
    Enqueue(Q,p);
    int wpl=0;//叶子结点带权路径长度和
    int lastVisit=1;//该层最右一个结点的编号
    int nowVisit=0,number=1;//nowVisit:现在刚弹出队列的结点编号，number现在入队的结点编号
    int deep=0;
    while(!empty(Q)){
        Dequeue(Q,p);
        nowVisit++;
        if(p->lchild==NULL&&p->rchild==NULL)
            wpl+=deep*p->weight;
        if(p->lchild){
            Enqueue(p->lchild);
            number++;
        }
        if(p->rchild){
            Enqueue(p->rchild);  
            number++;
        }
        if(lastVisit==nowVisit)
            lastVisit=number；
    }
    return wpl;
}