10.2路径

平衡二叉树，找路径，直接套板子

#include<bits/stdc++.h>
#define sf scanf
#define scf(x) scanf("%d",&x)
#define scff(x,y) scanf("%d%d",&x,&y)
#define scfff(x,y,z) scanf("%d%d%d",&x,&y,&z)
#define pf printf
#define prf(x) printf("%d\n",x)
#define mm(x,b) memset((x),(b),sizeof(x))
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=a;i>=n;i--)
typedef long long ll;
const ll mod=1e9+100;
const double eps=1e-8;
using namespace std;
const double pi=acos(-1.0);
const int inf=0xfffffff;
const int N=1e5+7;
struct node
{
	int lc,rc,h,v;
}tree[N];
int pos=0,x1,x2,root;
int right_rotate(int r)//zig右旋
{
	int t = tree[r].lc;
	tree[r].lc = tree[t].rc;
	tree[t].rc = r;
	tree[r].h = max(tree[tree[r].lc].h,tree[tree[r].rc].h)+1;
	tree[t].h = max(tree[tree[t].lc].h,tree[tree[t].rc].h)+1;
	return t;
}
int left_rotate(int r)//zag左旋
{
	int t = tree[r].rc;
	tree[r].rc = tree[t].lc;
	tree[t].lc = r;
	tree[r].h = max(tree[tree[r].lc].h,tree[tree[r].rc].h)+1;
	tree[t].h = max(tree[tree[t].lc].h,tree[tree[t].rc].h)+1;
	return t;
}
int right_left_rotate(int r)//zigzag双旋
{
	tree[r].rc = right_rotate(tree[r].rc);
	return left_rotate(r);
}
int left_right_rotate(int r)//zagzig双旋
{
	tree[r].lc = left_rotate(tree[r].lc);
	return right_rotate(r);
}
void maintain(int &r)
{
	if(tree[tree[r].lc].h == tree[tree[r].rc].h+2)//左子树高了
	{
		int t = tree[r].lc;
		if(tree[tree[t].lc].h == tree[tree[r].rc].h+1) r = right_rotate(r);//左子树的左儿子，对应第一种情况
		else if(tree[tree[t].rc].h == tree[tree[r].rc].h+1) r = left_right_rotate(r);	
	}
	else if(tree[tree[r].rc].h == tree[tree[r].lc].h+2)//右子树高了
	{
		int t = tree[r].rc;
		if(tree[tree[t].rc].h == tree[tree[r].lc].h+1) r = left_rotate(r);//右子树的右儿子，对应第四种情况
		else if(tree[tree[t].lc].h == tree[tree[r].lc].h+1) r = right_left_rotate(r);
	}
	tree[r].h = max(tree[tree[r].lc].h,tree[tree[r].rc].h)+1;//高度更新
}
void find(int x,int r)
{
	int v=tree[r].v;
	if(x==v) 
	{
		prf(x);
		return;
	}
	pf("%d ",v );
	if(x<v)
		find(x,tree[r].lc);
	else
		find(x,tree[r].rc);
}
int insert(int r,int x)
{
	if(r == 0)//找到一个空的节点，赋值
	{
		tree[++pos].h = 1;//高度初始化
		tree[pos].v = x;
		return pos;
	}
	if(x < tree[r].v) tree[r].lc = insert(tree[r].lc,x);//插入的数小于根节点，因此在它的左子树插入
	else if(x > tree[r].v) tree[r].rc = insert(tree[r].rc,x);
	maintain(r);//维持节点r的平衡
	return r;//返回新的根节点
}
int main()
{
	int n,aa,x;scf(n);
	while(n--)
	{
		scff(aa,x);
		if(aa==1)
			root=insert(root,x);	
		else
			find(x,root);
	}
	return 0;
}