Splay！

 #include<cstdio>
 #include<cstdlib>
 const int mod =;
 const int inf  = ~0u>>;
 const int maxn = ;
 int lim;
 struct SplayTree {
 .    int sz[maxn];
 .    int ch[maxn][];
 .    int pre[maxn];
 .    int rt,top;
 .    inline void up(int x){
 .        sz[x]  = cnt[x]  + sz[ ch[x][] ] + sz[ ch[x][] ];
 .    }
 .    inline void Rotate(int x,int f){
 .        int y=pre[x];
 .        ch[y][!f] = ch[x][f];
 .        pre[ ch[x][f] ] = y;
 .        pre[x] = pre[y];
 .        if(pre[x]) ch[ pre[y] ][ ch[pre[y]][] == y ] =x;
 .        ch[x][f] = y;
 .        pre[y] = x;
 .        up(y);
 .    }
 .    inline void Splay(int x,int goal){//将x旋转到goal的下面
 .        while(pre[x] != goal){
 .            if(pre[pre[x]] == goal) Rotate(x , ch[pre[x]][] == x);
 .            else   {
 .                int y=pre[x],z=pre[y];
 .                int f = (ch[z][]==y);
 .                if(ch[y][f] == x) Rotate(x,!f),Rotate(x,f);
 .                else Rotate(y,f),Rotate(x,f);
 .            }
 .        }
 .        up(x);
 .        if(goal==) rt=x;
 .    }
 .    inline void RTO(int k,int goal){//将第k位数旋转到goal的下面
 .        int x=rt;
 .        while(sz[ ch[x][] ] != k-) {
 .            if(k < sz[ ch[x][] ]+) x=ch[x][];
 .            else {
 .                k-=(sz[ ch[x][] ]+);
 .                x = ch[x][];
 .            }
 .        }
 .        Splay(x,goal);
 .    }
 .    inline void vist(int x){
 .        if(x){
 .            printf("结点%2d : 左儿子  %2d   右儿子  %2d   %2d sz=%d\n",x,ch[x][],ch[x][],val[x],sz[x]);
 .            vist(ch[x][]);
 .            vist(ch[x][]);
 .        }
 .    }
 .    inline void Newnode(int &x,int c){
 .        x=++top;
 .        ch[x][] = ch[x][] = pre[x] = ;
 .        sz[x]=; cnt[x]=;
 .        val[x] = c;
 .    }
 .    inline void init(){
 .        ans=;type=-;
 .        ch[][]=ch[][]=pre[]=sz[]=;
 .        rt=top=; cnt[]=;
 .        Newnode(rt,-inf);
 .        Newnode(ch[rt][],inf);
 .        pre[top]=rt;
 .        sz[rt]=;
 .    }
 .    inline void Insert(int &x,int key,int f){
 .        if(!x) {
 .            Newnode(x,key);
 .            pre[x]=f;
 .            Splay(x,);
 .            return ;
 .        }
 .        if(key==val[x]){
 .            cnt[x]++;
 .            sz[x]++;
 .            return ;
 .        }else if(key<val[x]) {
 .            Insert(ch[x][],key,x);
 .        } else {
 .            Insert(ch[x][],key,x);
 .        }
 .        up(x);
 .    }
 .    void Del(){
 .         int t=rt;
 .         if(ch[rt][]) {
 .             rt=ch[rt][];
 .             RTO(,);
 .             ch[rt][]=ch[t][];
 .             if(ch[rt][]) pre[ch[rt][]]=rt;
 .         }
 .         else rt=ch[rt][];
 .         pre[rt]=;
 .         up(rt);
 .    }
 .    void findpre(int x,int key,int &ans){
 .        if(!x)  return ;
 .        if(val[x] <= key){
 .            ans=x;
 .            findpre(ch[x][],key,ans);
 .        } else
 .            findpre(ch[x][],key,ans);
 .    }
 .    void findsucc(int x,int key,int &ans){
 .        if(!x) return ;
 .        if(val[x]>=key) {
 .            ans=x;
 .            findsucc(ch[x][],key,ans);
 .        } else
 .            findsucc(ch[x][],key,ans);
 .    }
 .    void solve() {
 .        int a,b,x,y;
 .        scanf("%d%d",&a,&b);
 .        if(a==type || sz[rt]==){
 .
 .            Insert(rt,b,),type=a;
 .            //printf("type=%d\n",type);
 .        }
 .        else {
 .            findpre(rt,b,x);
 .            findsucc(rt,b,y);
 .            if(abs(val[x]-b) <= abs(val[y]-b)) {
 .                ans+=abs(val[x]-b);
 .                ans%=mod;
 .                Splay(x,);
 .                Del();
 .            }
 .            else {
 .                ans+=abs(val[y]-b);
 .                ans%=mod;
 .                Splay(y,);
 .                Del();
 .            }
 .        }
 .        //spt.vist(rt);
 .    }
 .    int cnt[maxn];
 .    int val[maxn];
 .    int type;
 .    int ans;
 .}spt;
 .int main()
 .{
 .    int n;
 .    scanf("%d",&n);
 .    spt.init();
 .    while(n--)  spt.solve();
 .    printf("%d\n",spt.ans);
 .    return ;
 }