POJ3468/splay树/成段更新

板子题，正在努力看懂板子。。

http://blog.csdn.net/acm_cxlove/article/details/7815019

http://www.cnblogs.com/kuangbin/archive/2013/04/21/3034081.html

 #include <cstdio>
 #include <cstring>
 #include <algorithm>

 #define keyTree (ch[ ch[root][1] ][0])
 #define LL long long

 using namespace std;

 const int maxn = ;

 struct SpalyTree{
     int sz[maxn];
     int ch[maxn][];
     int pre[maxn];
     int root,top1,top2;
     int ss[maxn], que[maxn];

     void Rotate(int x,int f)
     {
         int y = pre[x];
         push_down(y);
         push_down(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;
         push_up(y);
     }
     void Splay(int x,int goal)
     {
         push_down(x);
         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);
                 }
             }
         }
         push_up(x);
         if(goal == ) root = x;
     }
     void RotateTo(int k,int goal)
     {
         int x = root;
         push_down(x);
         while(sz[ ch[x][] ] != k)
         {
             if(k < sz[ ch[x][] ])
             {
                 x = ch[x][];
             }
             else
             {
                 k -= (sz[ch[x][] ] + );
                 x = ch[x][];
             }
             push_down(x);
         }
         Splay(x,goal);
     }
     void erase(int x)
     {
         int father = pre[x];
         int head = ,tail = ;
         for(que[tail++] = x;head < tail;head++)
         {
             ss[top2++] = que[head];
             if(ch[que[head] ][]) que[tail++] = ch[que[head] ][];
             if(ch[que[head] ][]) que[tail++] = ch[que[head] ][];
         }
         ch[father ][ch[father][]==x ] = ;
         push_up(father);
     }
     void debug(){printf("%d\n",root);Treaval(root);}
     void Treaval(int x)
     {
         if(x)
         {
             Treaval(ch[x][]);
             printf("结点%2d:左儿子 %2d 右儿子 %2d 父结点 %2d size = %2d ,val = %2d\n",x,ch[x][],ch[x][],pre[x],sz[x],val[x]);
             Treaval(ch[x][]);
         }
     }
     void NewNode(int &x,int c)
     {
         if(top2) x = ss[--top2];
         else x = ++top1;
         ch[x][] = ch[x][] = pre[x] = ;
         sz[x] = ;

         val[x] = sum[x] = c;
         add[x] = ;
     }
     void push_down(int x)
     {
         if(add[x])
         {
             val[x] += add[x];
             add[ch[x][] ] += add[x];
             add[ch[x][] ] += add[x];
             sum[ch[x][] ] += (LL)sz[ch[x][] ]*add[x];
             sum[ch[x][] ] += (LL)sz[ch[x][] ]*add[x];
             add[x] = ;
         }
     }
     void push_up(int x)
     {
         sz[x] = +sz[ch[x][] ] + sz[ch[x][] ];
         sum[x] = add[x] + val[x] + sum[ch[x][] ] + sum[ch[x][] ];
     }
     void makeTree(int &x,int l,int r,int f)
     {
         if(l > r) return ;
         int m = (l+r)>>;
         NewNode(x,num[m]);
         makeTree(ch[x][],l,m-,x);
         makeTree(ch[x][],m+,r,x);
         pre[x] = f;
         push_up(x);
     }
     void init(int n)
     {
         ch[][] = ch[][] = pre[] = sz[] = ;
         add[] = sum[] = ;

         root = top1 = ;
         NewNode(root, -);
         NewNode(ch[root][],-);
         pre[top1] = root;
         sz[root] = ;

         for(int i=;i<n;i++)
             scanf("%d",&num[i]);
         makeTree(keyTree,,n-,ch[root][]);
         push_up(ch[root][]);
         push_up(root);
     }
     void update()
     {
         int l,r,c;
         scanf("%d%d%d",&l,&r,&c);
         RotateTo(l-,);
         RotateTo(r+,root);
         add[keyTree] += c;
         sum[keyTree] += (LL)c*sz[keyTree];
     }
     void query()
     {
         int l,r;
         scanf("%d%d",&l,&r);
         RotateTo(l-,);
         RotateTo(r+,root);
         printf("%lld\n",sum[keyTree]);
     }

     int num[maxn];
     int val[maxn];
     int add[maxn];
     LL  sum[maxn];
 }spt;

 int n,m;

 int main()
 {
     while(~scanf("%d%d",&n,&m))
     {
         spt.init(n);
         char op[];
         for(int i=;i<m;i++)
         {
             scanf("%s",op);
             if(op[] == 'Q')
             {
                 spt.query();
             }
             else
                 spt.update();
         }
     }
 }