#include<iostream>
#include<cstring>
#include<cstdio>
#include<cstring>
using namespace std;
struct node
{ int data,rev,sum;
node *son[2],*pre;
bool judge();
bool isroot();
void pushdown();
void update();
void setson(node *child,int lr);}
lct[233];int top,a,b;
node *getnew(int x)
{ node *now=lct+ ++top;
now->data=x;
now->pre=now->son[1]=now->son[0]=lct;
now->sum=0; now->rev=0;
return now;}
bool node::judge()
{return pre->son[1]==this;}
bool node::isroot()
{ if(pre==lct)return true;
return !(pre->son[1]==this||pre->son[0]==this);}
void node::pushdown()
{ if(this==lct||!rev)return;
swap(son[0],son[1]);
son[0]->rev^=1;
son[1]->rev^=1;
rev=0;}
void node::update()
{sum=son[1]->sum+son[0]->sum+data;}
void node::setson(node *child,int lr)
{ this->pushdown();
child->pre=this;
son[lr]=child;
this->update();}
void rotate(node *now)
{ node *father=now->pre,*grandfa=father->pre;
if(!father->isroot()) grandfa->pushdown();
father->pushdown();
now->pushdown();
int lr=now->judge();
father->setson(now->son[lr^1],lr);
if(father->isroot()) now->pre=grandfa;
else grandfa->setson(now,father->judge());
now->setson(father,lr^1);
father->update();now->update();
if(grandfa!=lct) grandfa->update();}
void splay(node *now)
{ if(now->isroot())return;
for(;!now->isroot();rotate(now))
if(!now->pre->isroot())
now->judge()==now->pre->judge()?rotate(now->pre):rotate(now);}
node *access(node *now)
{ node *last=lct;
for(;now!=lct;last=now,now=now->pre)
{ splay(now); now->setson(last,1); } return last;}
void changeroot(node *now)
{ access(now)->rev^=1;
splay(now);}
void connect(node *x,node *y)
{ changeroot(x);
x->pre=y;
access(x);}
void cut(node *x,node *y)
{ changeroot(x);
access(y);
splay(x);
x->pushdown();
x->son[1]=y->pre=lct;
x->update();}
int query(node *x,node *y)
{ changeroot(x);
node *now=access(y);
return now->sum;}
int main()
{ scanf("%d%d",&a,&b);
node *A=getnew(a);
node *B=getnew(b);
connect(A,B);
cut(A,B);
connect(A,B);
printf("%d\n",query(A,B));
return 0;}

三楼提示：别看了。只是个a+b problem哦

大佬链接没了

请问大大，你发来这些该怎么操作需要下载什么软件辅助吗？

我把楼上的总结了一下自己也
链接是:网页链接
提取码是:1uwb

1uwb

感谢大佬

感谢大佬+1

这个只更新到557
最新的epub在这里：
https://tieba.baidu.com/p/7368633956