HDU 3966 Aragorn's Story 树链剖分

Link: http://acm.hdu.edu.cn/showproblem.php?pid=3966

这题注意要手动扩栈。

这题我交g++无限RE，即使手动扩栈了，但交C++就过了。

 #pragma comment(linker, "/STACK:1024000000,1024000000")
 #include <cstdio>
 #include <cstring>
 #include <iostream>
 #include <algorithm>
 #include <string>
 #include <vector>
 #include <map>
 using namespace std;
 const int maxn = 5e4+;
 #ifdef WIN32
     #define LL __int64
 #else
     #define LL long long
 #endif

 int A[maxn],totw;
 struct node
 {
     int fa,son,top,w,size,deep;
 }tree[maxn];
 vector<int> vt[maxn];
 int tr[maxn];

 void dfs_1(int p,int last,int de)
 {
     tree[p].son = -;
     tree[p].fa = last;
     tree[p].deep = de;
     tree[p].size = ;
     int num = vt[p].size();
     for(int i = ;i < num;++i)
         if(vt[p][i] != last)
         {
             dfs_1(vt[p][i],p,de+);
             tree[p].size += tree[vt[p][i]].size;
             if(- == tree[p].son || tree[vt[p][i]].size > tree[tree[p].son].size)
                 tree[p].son = vt[p][i];
         }
 }
 void dfs_2(int p,int top)
 {
     tree[p].w = ++totw;
     tree[p].top = top;
     if(tree[p].son != -)
         dfs_2(tree[p].son,top);
     else return ;
     int num = vt[p].size();
     for(int i = ;i < num;++i)
     {
         if(vt[p][i] != tree[p].fa && vt[p][i] != tree[p].son)
             dfs_2(vt[p][i],vt[p][i]);
     }
 }

 void sol()
 {
     totw = ;
     memset(tr,,sizeof(tr));
     memset(tree,,sizeof(tree));
     dfs_1(,,);
     dfs_2(,);
 }
 int lowbit(int x)
 {
     return x & (-x);
 }
 int query(int p)
 {
     p = tree[p].w;
     int tot = ;
     while(p >= )
     {
         tot += tr[p];
         p -= lowbit(p);
     }
     return tot;
 }
 void add(int n,int p,int d)
 {
     while(p <= n)
     {
         tr[p] += d;
         p += lowbit(p);
     }
 }
 void update_sec(int n,int u,int v,int d)
 {
     if(tree[u].w > tree[v].w) swap(u,v);
     add(n,tree[u].w,d);
     add(n,tree[v].w+,-d);
 }
 void update(int n,int u,int v,int d)
 {
     /*
     u,v不断靠近根结点
     */
     while(tree[u].top != tree[v].top)
     {
         if(tree[tree[u].top].deep < tree[tree[v].top].deep) swap(u,v);
         update_sec(n,tree[u].top,u,d);
         u = tree[tree[u].top].fa;
     }
     update_sec(n,u,v,d);
 }

 int main()
 {
 //    freopen("in.txt","r",stdin);
     int n,m,p;
     while(scanf("%d%d%d",&n,&m,&p)!=EOF)
     {
         for(int i = ;i <= n;++i)
             scanf("%d",&A[i]);
         for(int i = ;i <= n;++i)
             vt[i].clear();
         int x,y;
         for(int i = ;i < m;++i)
         {
             scanf("%d%d",&x,&y);
             vt[x].push_back(y);
             vt[y].push_back(x);
         }
         sol();
         char oper[];
         while(p--)
         {
             scanf("%s",oper);
             int x,y,z;
             if('Q' == oper[])
             {
                 scanf("%d",&x);
                 printf("%d\n",A[x] + query(x));
             }
             else if('I' == oper[])
             {
                 scanf("%d%d%d",&x,&y,&z);
                 update(n,x,y,z);
             }
             else if('D' == oper[])
             {
                 scanf("%d%d%d",&x,&y,&z);
                 update(n,x,y,-z);
             }
         }
     }
     return ;
 }