Hiho 1232 北京网络赛 F Couple Trees

给两颗标号从1...n的树，保证标号小的点一定在上面。每次询问A树上的x点，和B树上的y点同时向上走，最近的相遇点和x,y到这个点的距离。

比赛的时候想用倍增LCA做，但写渣了。。。。后来看到题解是主席树就写了一发

呆马：

  1 #include <iostream>
  2 #include <cstdio>
  3 #include <algorithm>
  4 #include <cstring>
  5 #include <cmath>
  6 #include <vector>
  7 #define inf 1000000007
  8 #define maxn 100020
  9 #define maxm 4200
 10 
 11 using namespace std;
 12 
 13 int fa[maxn],ga[maxn],ll[maxn],rr[maxn],dep[maxn],gap[maxn];
 14 int n,m,cnt;
 15 
 16 struct node
 17 {
 18     node *lc, *rc;
 19     int key, cov;
 20     node(){
 21         key=0;
 22         cov=0;
 23         lc=rc=NULL;
 24     }
 25 };
 26 
 27 struct ChairManTree
 28 {
 29     node *tree,*rot[maxn];
 30     int tot;
 31     node *new_node(){ return &tree[++tot];}
 32     node *build(int l, int r)
 33     {
 34         node *now=new_node();
 35         now->cov=now->key=0;
 36         if (l==r) return now;
 37         int mid=(l+r)>>1;
 38         now->lc=build(l,mid);
 39         now->rc=build(mid+1,r);
 40         return now;
 41     }
 42 
 43     void down(node *p)
 44     {
 45         if (p->cov)
 46         {
 47             node *nl=new_node();
 48             node *nr=new_node();
 49             *nl=*p->lc;
 50             *nr=*p->rc;
 51             nl->key=max(p->lc->key,p->cov);
 52             nl->cov=max(p->lc->cov,p->cov);
 53             nr->key=max(p->rc->key,p->cov);
 54             nr->cov=max(p->rc->cov,p->cov);
 55             p->lc=nl;
 56             p->rc=nr;
 57             p->cov=0;
 58         }
 59     }
 60 
 61     node *change(node *p, int l, int r, int ll, int rr, int x)
 62     {
 63         node *now=new_node();
 64         if (ll<=l && r<=rr)
 65         {
 66             *now=*p;
 67             now->key=max(now->key,x);
 68             now->cov=max(now->cov,x);
 69             return now;
 70         }
 71         down(p);
 72         *now=*p;
 73         int mid=(l+r)>>1;
 74         if (ll<=mid) now->lc=change(p->lc, l, mid, ll, rr, x);
 75         if (rr>mid) now->rc=change(p->rc, mid+1, r, ll, rr, x);
 76         return now;
 77     }
 78 
 79     int query(node *now, int l, int r, int x)
 80     {
 81         if (l==r) return now->key;
 82         down(now);
 83         int mid=(l+r)>>1;
 84         if (x<=mid) return query(now->lc, l, mid, x);
 85         else return query(now->rc, mid+1, r, x);
 86     }
 87 
 88     void write(node *now,int l,int r)
 89     {
 90         if (l==r)
 91         {
 92             cout<<now->key;
 93             return ;
 94         }
 95         down(now);
 96         int mid=(l+r)>>1;
 97         write(now->lc,l,mid);
 98         write(now->rc,mid+1,r);
 99     }
100 
101     void init(int n)
102     {
103         tree=new node[n*80];
104         tot=0;
105     }
106     void clear()
107     {
108         delete [] tree;
109     }
110 }s;
111 
112 vector<int> e[maxn];
113 
114 void dfs(int x)
115 {
116     ll[x]=++cnt;
117     int n=e[x].size();
118     for (int i=0;i<n;i++)
119     {
120         int k=e[x][i];
121         dfs(k);
122     }
123     rr[x]=cnt;
124 }
125 
126 int main()
127 {
128     //freopen("F.in","r",stdin);
129     while (scanf("%d%d",&n,&m)!=EOF)
130     {
131         s.init(n);
132         fa[1]=ga[1]=0;
133         dep[1]=gap[1]=1;
134         for (int i=1;i<=n;i++) e[i].clear();
135         for (int i=2;i<=n;i++) scanf("%d",&fa[i]), e[fa[i]].push_back(i), dep[i]=dep[fa[i]]+1;
136         for (int i=2;i<=n;i++) scanf("%d",&ga[i]), gap[i]=gap[ga[i]]+1;
137         cnt=0;
138         dfs(1);
139         
140         s.rot[0]=s.build(1,n);
141         
142         for (int i=1;i<=n;i++)
143             s.rot[i]=s.change(s.rot[ga[i]],1,n,ll[i],rr[i],i);
144         int x,y,ans=0;
145         for (int i=1;i<=m;i++)
146         {
147             scanf("%d%d",&x,&y);
148             x=(x+ans)%n+1, y=(y+ans)%n+1;
149             ans=s.query(s.rot[y],1,n,ll[x]);
150             printf("%d %d %d\n",ans,dep[x]-dep[ans]+1, gap[y]-gap[ans]+1);
151         }
152         s.clear();
153     }
154     return 0;
155 }

couple tree

posted @ 2015-10-02 19:27 Zig_zag 阅读(433) 评论(0) 编辑收藏举报

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