遞迴，給你個思路吧

1、求葉子個數

//Node為二叉樹節點型別,呼叫時引數為樹的根num(root);

intnum(Node*node)

{

if(node==NULL)return0;

return1+num(node->left)+num(node->right);

}

2、高度

intheight(Node*node)

{

if(node==NULL)return0;

else

{

intx=height(node->right);

inty=height(node->left);

if(x>y)returnx+1;

elsereturny+1;

}

}

3、複製

Node*copy(Node*node)

{

if(node==NULL)returnNULL;

Node*left=copy(node->left);

Node*right=copy(node->right);

Node*newnode=(Node*)malloc(sizeof(Node));

newnode->val=node->val;

newnode->left=left;

newnode->right=right;

returnnewnode;

}