树链剖分

Heavy-Light Decomposition 有图有真相：http://blog.sina.com.cn/s/blog_a19ad7a10102uz6f.html

375. Query on a tree http://www.spoj.com/problems/QTREE/

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int M=10010;
 12 struct IN{
 13     int u,v,w;
 14 }e[M];
 15 struct G{
 16     struct E{
 17         int v,next;
 18     }e[M<<1];
 19     int le,head[M];
 20     void init(){
 21         le=0;
 22         mt(head,-1);
 23     }
 24     void add(int u,int v){
 25         e[le].v=v;
 26         e[le].next=head[u];
 27         head[u]=le++;
 28     }
 29 }g;
 30 int n,fa[M],dep[M],num[M],son[M],sid[M],top[M];
 31 void dfs(int u){
 32     num[u]=1;
 33     son[u]=0;
 34     for(int i=g.head[u];~i;i=g.e[i].next){
 35         int v=g.e[i].v;
 36         if(v!=fa[u]){
 37             fa[v]=u;
 38             dep[v]=dep[u]+1;
 39             dfs(v);
 40             if(num[son[u]]<num[v]) son[u]=v;
 41             num[u]+=num[v];
 42         }
 43     }
 44 }
 45 void get(int u,int Top){
 46     sid[u]=++n;
 47     top[u]=Top;
 48     if(son[u]) get(son[u],Top);
 49     for(int i=g.head[u];~i;i=g.e[i].next){
 50         int v=g.e[i].v;
 51         if(v!=fa[u]&&v!=son[u]){
 52             get(v,v);
 53         }
 54     }
 55 }
 56 int tree[M<<2];
 57 void pushup(int rt){
 58     tree[rt]=max(tree[rt<<1],tree[rt<<1|1]);
 59 }
 60 void update(int x,int val,lrrt){
 61     if(L==R){
 62         tree[rt]=val;
 63         return ;
 64     }
 65     imid;
 66     if(mid>=x) update(x,val,lson);
 67     else       update(x,val,rson);
 68     pushup(rt);
 69 }
 70 int query(int x,int y,lrrt){
 71     if(x<=L&&R<=y) return tree[rt];
 72     imid;
 73     int ans=0;
 74     if(mid>=x) ans=max(ans,query(x,y,lson));
 75     if(mid<y)  ans=max(ans,query(x,y,rson));
 76     return ans;
 77 }
 78 int solve(int x,int y){
 79     int tx=top[x],ty=top[y],ans=0;
 80     while(tx!=ty){
 81         if(dep[tx]<dep[ty]){
 82             swap(tx,ty);
 83             swap(x,y);
 84         }
 85         ans=max(ans,query(sid[tx],sid[x],iall));
 86         x=fa[tx];
 87         tx=top[x];
 88     }
 89     if(x==y) return ans;
 90     if(dep[x]>dep[y]) swap(x,y);
 91     return max(ans,query(sid[son[x]],sid[y],iall));
 92 }
 93 int main(){
 94     int t,m;
 95     while(~scanf("%d",&t)){
 96         while(t--){
 97             scanf("%d",&m);
 98             g.init();
 99             for(int i=1;i<m;i++){
100                 scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].w);
101                 g.add(e[i].u,e[i].v);
102                 g.add(e[i].v,e[i].u);
103             }
104             n=fa[1]=dep[1]=num[0]=1;
105             dfs(1);
106             get(1,1);
107             mt(tree,0);
108             for(int i=1;i<m;i++){
109                 if(dep[e[i].u]>dep[e[i].v]){
110                     swap(e[i].u,e[i].v);
111                 }
112                 update(sid[e[i].v],e[i].w,iall);
113             }
114             char op[8];
115             int x,y;
116             while(scanf("%s",op),op[0]!='D'){
117                 scanf("%d%d",&x,&y);
118                 if(op[0]=='C') update(sid[e[x].v],y,iall);
119                 else printf("%d\n",solve(x,y));
120             }
121         }
122     }
123     return 0;
124 }

View Code

Tree http://poj.org/problem?id=3237

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int inf=0x7fffffff;
 12 const int M=10010;
 13 struct IN{
 14     int u,v,w;
 15 }e[M];
 16 struct G{
 17     struct E{
 18         int v,next;
 19     }e[M<<1];
 20     int le,head[M];
 21     void init(){
 22         le=0;
 23         mt(head,-1);
 24     }
 25     void add(int u,int v){
 26         e[le].v=v;
 27         e[le].next=head[u];
 28         head[u]=le++;
 29     }
 30 }g;
 31 int n,fa[M],dep[M],num[M],son[M],top[M],sid[M];
 32 void dfs(int u){
 33     num[u]=1;
 34     son[u]=0;
 35     for(int i=g.head[u];~i;i=g.e[i].next){
 36         int v=g.e[i].v;
 37         if(v!=fa[u]){
 38             fa[v]=u;
 39             dep[v]=dep[u]+1;
 40             dfs(v);
 41             if(num[son[u]]<num[v]) son[u]=v;
 42             num[u]+=num[v];
 43         }
 44     }
 45 }
 46 void get(int u,int Top){
 47     sid[u]=++n;
 48     top[u]=Top;
 49     if(son[u]) get(son[u],Top);
 50     for(int i=g.head[u];~i;i=g.e[i].next){
 51         int v=g.e[i].v;
 52         if(v!=fa[u]&&v!=son[u]){
 53             get(v,v);
 54         }
 55     }
 56 }
 57 struct T{
 58     int big,sma,lazy;
 59 }tree[M<<2];
 60 void pushup(int rt){
 61     tree[rt].big=max(tree[rt<<1].big,tree[rt<<1|1].big);
 62     tree[rt].sma=min(tree[rt<<1].sma,tree[rt<<1|1].sma);
 63 }
 64 void pushdown(int rt){
 65     if(tree[rt].lazy){
 66         tree[rt<<1].lazy^=1;
 67         tree[rt<<1|1].lazy^=1;
 68         tree[rt].lazy=0;
 69         tree[rt<<1].big*=-1;
 70         tree[rt<<1].sma*=-1;
 71         swap(tree[rt<<1].big,tree[rt<<1].sma);
 72         tree[rt<<1|1].big*=-1;
 73         tree[rt<<1|1].sma*=-1;
 74         swap(tree[rt<<1|1].big,tree[rt<<1|1].sma);
 75     }
 76 }
 77 void update(int x,int val,lrrt){
 78     if(L==R){
 79         tree[rt].big=tree[rt].sma=val;
 80         return ;
 81     }
 82     pushdown(rt);
 83     imid;
 84     if(mid>=x) update(x,val,lson);
 85     else       update(x,val,rson);
 86     pushup(rt);
 87 }
 88 void change(int x,int y,lrrt){
 89     if(x<=L&&R<=y){
 90         tree[rt].lazy^=1;
 91         tree[rt].big*=-1;
 92         tree[rt].sma*=-1;
 93         swap(tree[rt].big,tree[rt].sma);
 94         return ;
 95     }
 96     pushdown(rt);
 97     imid;
 98     if(mid>=x) change(x,y,lson);
 99     if(mid<y)  change(x,y,rson);
100     pushup(rt);
101 }
102 void work(int x,int y){
103     int tx=top[x],ty=top[y];
104     while(tx!=ty){
105         if(dep[tx]<dep[ty]){
106             swap(tx,ty);
107             swap(x,y);
108         }
109         change(sid[tx],sid[x],iall);
110         x=fa[tx];
111         tx=top[x];
112     }
113     if(x==y) return ;
114     if(dep[x]>dep[y]) swap(x,y);
115     change(sid[son[x]],sid[y],iall);
116 }
117 int query(int x,int y,lrrt){
118     if(x<=L&&R<=y) return tree[rt].big;
119     pushdown(rt);
120     imid;
121     int ans=-inf;
122     if(mid>=x) ans=max(ans,query(x,y,lson));
123     if(mid<y)  ans=max(ans,query(x,y,rson));
124     return ans;
125 }
126 int getmax(int x,int y){
127     int tx=top[x],ty=top[y],ans=-inf;
128     while(tx!=ty){
129         if(dep[tx]<dep[ty]){
130             swap(tx,ty);
131             swap(x,y);
132         }
133         ans=max(ans,query(sid[tx],sid[x],iall));
134         x=fa[tx];
135         tx=top[x];
136     }
137     if(x==y) return ans;
138     if(dep[x]>dep[y]) swap(x,y);
139     return max(ans,query(sid[son[x]],sid[y],iall));
140 }
141 int main(){
142     int t,m;
143     while(~scanf("%d",&t)){
144         while(t--){
145             scanf("%d",&m);
146             g.init();
147             for(int i=1;i<m;i++){
148                 scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].w);
149                 g.add(e[i].u,e[i].v);
150                 g.add(e[i].v,e[i].u);
151             }
152             n=fa[1]=dep[1]=num[0]=0;
153             dfs(1);
154             get(1,1);
155             mt(tree,0);
156             for(int i=1;i<m;i++){
157                 if(dep[e[i].u]>dep[e[i].v]){
158                     swap(e[i].u,e[i].v);
159                 }
160                 update(sid[e[i].v],e[i].w,iall);
161             }
162             char op[8];
163             int x,y;
164             while(scanf("%s",op),op[0]!='D'){
165                 scanf("%d%d",&x,&y);
166                 if(op[0]=='C') update(sid[e[x].v],y,iall);
167                 else if(op[0]=='N') work(x,y);
168                 else printf("%d\n",getmax(x,y));
169             }
170         }
171     }
172     return 0;
173 }

View Code

Aragorn's Story http://acm.hdu.edu.cn/showproblem.php?pid=3966

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int M=50010;
 12 struct G{
 13     struct E{
 14         int v,next;
 15     }e[M<<1];
 16     int le,head[M];
 17     void init(){
 18         le=0;
 19         mt(head,-1);
 20     }
 21     void add(int u,int v){
 22         e[le].v=v;
 23         e[le].next=head[u];
 24         head[u]=le++;
 25     }
 26 }g;
 27 int n,val[M],fa[M],dep[M],num[M],son[M],top[M],sid[M];
 28 void dfs(int u){
 29     num[u]=1;
 30     son[u]=0;
 31     for(int i=g.head[u];~i;i=g.e[i].next){
 32         int v=g.e[i].v;
 33         if(v!=fa[u]){
 34             fa[v]=u;
 35             dep[v]=dep[u]+1;
 36             dfs(v);
 37             if(num[son[u]]<num[v]) son[u]=v;
 38             num[u]+=num[v];
 39         }
 40     }
 41 }
 42 void get(int u,int Top){
 43     sid[u]=++n;
 44     top[u]=Top;
 45     if(son[u]) get(son[u],top[u]);
 46     for(int i=g.head[u];~i;i=g.e[i].next){
 47         int v=g.e[i].v;
 48         if(v!=fa[u]&&v!=son[u]){
 49             get(v,v);
 50         }
 51     }
 52 }
 53 int tree[M<<2];
 54 void pushdown(int rt){
 55     if(tree[rt]){
 56         tree[rt<<1]+=tree[rt];
 57         tree[rt<<1|1]+=tree[rt];
 58         tree[rt]=0;
 59     }
 60 }
 61 void update(int x,int y,int z,lrrt){
 62     if(x<=L&&R<=y){
 63         tree[rt]+=z;
 64         return ;
 65     }
 66     imid;
 67     pushdown(rt);
 68     if(mid>=x) update(x,y,z,lson);
 69     if(mid<y)  update(x,y,z,rson);
 70 }
 71 int query(int x,lrrt){
 72     if(L==R) return tree[rt];
 73     pushdown(rt);
 74     imid;
 75     if(mid>=x) return query(x,lson);
 76     return query(x,rson);
 77 }
 78 void work(int x,int y,int z){
 79     int tx=top[x],ty=top[y];
 80     while(tx!=ty){
 81         if(dep[tx]<dep[ty]){
 82             swap(tx,ty);
 83             swap(x,y);
 84         }
 85         update(sid[tx],sid[x],z,iall);
 86         x=fa[tx];
 87         tx=top[x];
 88     }
 89     if(dep[x]>dep[y]) swap(x,y);
 90     update(sid[x],sid[y],z,iall);
 91 }
 92 int main(){
 93     int m,p;
 94     while(~scanf("%d%d%d",&n,&m,&p)){
 95         for(int i=1;i<=n;i++){
 96             scanf("%d",&val[i]);
 97         }
 98         g.init();
 99         for(int i=0,u,v;i<m;i++){
100             scanf("%d%d",&u,&v);
101             g.add(u,v);
102             g.add(v,u);
103         }
104         n=fa[1]=dep[1]=num[0]=0;
105         dfs(1);
106         get(1,1);
107         mt(tree,0);
108         for(int i=1;i<=m+1;i++){
109             update(sid[i],sid[i],val[i],iall);
110         }
111         char op[2];
112         while(p--){
113             int x,y,z;
114             scanf("%s%d",op,&x);
115             if(op[0]=='Q'){
116                 printf("%d\n",query(sid[x],iall));
117                 continue;
118             }
119             scanf("%d%d",&y,&z);
120             if(op[0]=='D') z*=-1;
121             work(x,y,z);
122         }
123     }
124     return 0;
125 }

View Code

1036: [ZJOI2008]树的统计Count http://www.lydsy.com/JudgeOnline/problem.php?id=1036

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int inf=0x7fffffff;
 12 const int M=30010;
 13 struct G{
 14     struct E{
 15         int v,next;
 16     }e[M<<1];
 17     int le,head[M];
 18     void init(){
 19         le=0;
 20         mt(head,-1);
 21     }
 22     void add(int u,int v){
 23         e[le].v=v;
 24         e[le].next=head[u];
 25         head[u]=le++;
 26     }
 27 }g;
 28 int n,fa[M],dep[M],num[M],son[M],sid[M],top[M];
 29 void dfs(int u){
 30     num[u]=1;
 31     son[u]=0;
 32     for(int i=g.head[u];~i;i=g.e[i].next){
 33         int v=g.e[i].v;
 34         if(v!=fa[u]){
 35             fa[v]=u;
 36             dep[v]=dep[u]+1;
 37             dfs(v);
 38             if(num[son[u]]<num[v]) son[u]=v;
 39             num[u]+=num[v];
 40         }
 41     }
 42 }
 43 void get(int u,int Top){
 44     sid[u]=++n;
 45     top[u]=Top;
 46     if(son[u]) get(son[u],Top);
 47     for(int i=g.head[u];~i;i=g.e[i].next){
 48         int v=g.e[i].v;
 49         if(v!=fa[u]&&v!=son[u]){
 50             get(v,v);
 51         }
 52     }
 53 }
 54 struct T{
 55     int big,sum;
 56 }tree[M<<2];
 57 void pushup(int rt){
 58     tree[rt].sum=tree[rt<<1].sum+tree[rt<<1|1].sum;
 59     tree[rt].big=max(tree[rt<<1].big,tree[rt<<1|1].big);
 60 }
 61 void update(int x,int val,lrrt){
 62     if(L==R){
 63         tree[rt].big=tree[rt].sum=val;
 64         return ;
 65     }
 66     imid;
 67     if(mid>=x) update(x,val,lson);
 68     else       update(x,val,rson);
 69     pushup(rt);
 70 }
 71 int sum(int x,int y,lrrt){
 72     if(x<=L&&R<=y) return tree[rt].sum;
 73     imid;
 74     int ans=0;
 75     if(mid>=x) ans+=sum(x,y,lson);
 76     if(mid<y)  ans+=sum(x,y,rson);
 77     return ans;
 78 }
 79 int getsum(int x,int y){
 80     int tx=top[x],ty=top[y],ans=0;
 81     while(tx!=ty){
 82         if(dep[tx]<dep[ty]){
 83             swap(tx,ty);
 84             swap(x,y);
 85         }
 86         ans+=sum(sid[tx],sid[x],iall);
 87         x=fa[tx];
 88         tx=top[x];
 89     }
 90     if(dep[x]>dep[y]) swap(x,y);
 91     return ans+sum(sid[x],sid[y],iall);
 92 }
 93 int query(int x,int y,lrrt){
 94     if(x<=L&&R<=y) return tree[rt].big;
 95     imid;
 96     int ans=-inf;
 97     if(mid>=x) ans=max(ans,query(x,y,lson));
 98     if(mid<y)  ans=max(ans,query(x,y,rson));
 99     return ans;
100 }
101 int getmax(int x,int y){
102     int tx=top[x],ty=top[y],ans=-inf;
103     while(tx!=ty){
104         if(dep[tx]<dep[ty]){
105             swap(tx,ty);
106             swap(x,y);
107         }
108         ans=max(ans,query(sid[tx],sid[x],iall));
109         x=fa[tx];
110         tx=top[x];
111     }
112     if(dep[x]>dep[y]) swap(x,y);
113     return max(ans,query(sid[x],sid[y],iall));
114 }
115 int main(){
116     int m;
117     while(~scanf("%d",&m)){
118         g.init();
119         for(int i=0,u,v;i<m-1;i++){
120             scanf("%d%d",&u,&v);
121             g.add(u,v);
122             g.add(v,u);
123         }
124         n=fa[1]=dep[1]=num[0]=0;
125         dfs(1);
126         get(1,1);
127         mt(tree,0);
128         for(int i=1,x;i<=m;i++){
129             scanf("%d",&x);
130             update(sid[i],x,iall);
131         }
132         scanf("%d",&m);
133         char op[8];
134         int x,y;
135         while(m--){
136             scanf("%s%d%d",op,&x,&y);
137             if(op[0]=='C') update(sid[x],y,iall);
138             else if(op[1]=='M') printf("%d\n",getmax(x,y));
139             else printf("%d\n",getsum(x,y));
140         }
141     }
142     return 0;
143 }

View Code

Problem 2082 过路费 http://acm.fzu.edu.cn/problem.php?pid=2082

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 typedef __int64 LL;
 12 const int M=50010;
 13 struct IN{
 14     int u,v,w;
 15 }e[M];
 16 struct G{
 17     struct E{
 18         int v,next;
 19     }e[M<<1];
 20     int le,head[M];
 21     void init(){
 22         le=0;
 23         mt(head,-1);
 24     }
 25     void add(int u,int v){
 26         e[le].v=v;
 27         e[le].next=head[u];
 28         head[u]=le++;
 29     }
 30 }g;
 31 int n,fa[M],dep[M],num[M],son[M],sid[M],top[M];
 32 void dfs(int u){
 33     num[u]=1;
 34     son[u]=0;
 35     for(int i=g.head[u];~i;i=g.e[i].next){
 36         int v=g.e[i].v;
 37         if(v!=fa[u]){
 38             fa[v]=u;
 39             dep[v]=dep[u]+1;
 40             dfs(v);
 41             if(num[son[u]]<num[v]) son[u]=v;
 42             num[u]+=num[v];
 43         }
 44     }
 45 }
 46 void get(int u,int Top){
 47     sid[u]=++n;
 48     top[u]=Top;
 49     if(son[u]) get(son[u],Top);
 50     for(int i=g.head[u];~i;i=g.e[i].next){
 51         int v=g.e[i].v;
 52         if(v!=fa[u]&&v!=son[u]){
 53             get(v,v);
 54         }
 55     }
 56 }
 57 LL tree[M<<2];
 58 void pushup(int rt){
 59     tree[rt]=tree[rt<<1]+tree[rt<<1|1];
 60 }
 61 void update(int x,int val,lrrt){
 62     if(L==R){
 63         tree[rt]=val;
 64         return ;
 65     }
 66     imid;
 67     if(mid>=x) update(x,val,lson);
 68     else       update(x,val,rson);
 69     pushup(rt);
 70 }
 71 LL query(int x,int y,lrrt){
 72     if(x<=L&&R<=y) return tree[rt];
 73     imid;
 74     LL ans=0;
 75     if(mid>=x) ans+=query(x,y,lson);
 76     if(mid<y)  ans+=query(x,y,rson);
 77     return ans;
 78 }
 79 LL getsum(int x,int y){
 80     int tx=top[x],ty=top[y];
 81     LL ans=0;
 82     while(tx!=ty){
 83         if(dep[tx]<dep[ty]){
 84             swap(tx,ty);
 85             swap(x,y);
 86         }
 87         ans+=query(sid[tx],sid[x],iall);
 88         x=fa[tx];
 89         tx=top[x];
 90     }
 91     if(x==y) return ans;
 92     if(dep[x]>dep[y]) swap(x,y);
 93     return ans+query(sid[son[x]],sid[y],iall);
 94 }
 95 int main(){
 96     int m,q;
 97     while(~scanf("%d%d",&m,&q)){
 98         g.init();
 99         for(int i=1;i<m;i++){
100             scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].w);
101             g.add(e[i].u,e[i].v);
102             g.add(e[i].v,e[i].u);
103         }
104         n=fa[1]=dep[1]=num[0]=0;
105         dfs(1);
106         get(1,1);
107         mt(tree,0);
108         for(int i=1;i<m;i++){
109             if(dep[e[i].u]>dep[e[i].v]){
110                 swap(e[i].u,e[i].v);
111             }
112             update(sid[e[i].v],e[i].w,iall);
113         }
114         while(q--){
115             int op,x,y;
116             scanf("%d%d%d",&op,&x,&y);
117             if(!op) update(sid[e[x].v],y,iall);
118             else printf("%I64d\n",getsum(x,y));
119         }
120     }
121     return 0;
122 }

View Code

Housewife Wind http://poj.org/problem?id=2763

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int M=100010;
 12 struct IN{
 13     int u,v,w;
 14 }e[M];
 15 struct G{
 16     struct E{
 17         int v,next;
 18     }e[M<<1];
 19     int le,head[M];
 20     void init(){
 21         le=0;
 22         mt(head,-1);
 23     }
 24     void add(int u,int v){
 25         e[le].v=v;
 26         e[le].next=head[u];
 27         head[u]=le++;
 28     }
 29 }g;
 30 int n,fa[M],dep[M],num[M],son[M],sid[M],top[M];
 31 void dfs(int u){
 32     num[u]=1;
 33     son[u]=0;
 34     for(int i=g.head[u];~i;i=g.e[i].next){
 35         int v=g.e[i].v;
 36         if(v!=fa[u]){
 37             fa[v]=u;
 38             dep[v]=dep[u]+1;
 39             dfs(v);
 40             if(num[son[u]]<num[v]) son[u]=v;
 41             num[u]+=num[v];
 42         }
 43     }
 44 }
 45 void get(int u,int Top){
 46     sid[u]=++n;
 47     top[u]=Top;
 48     if(son[u]) get(son[u],Top);
 49     for(int i=g.head[u];~i;i=g.e[i].next){
 50         int v=g.e[i].v;
 51         if(v!=fa[u]&&v!=son[u]){
 52             get(v,v);
 53         }
 54     }
 55 }
 56 int tree[M<<2];
 57 void pushup(int rt){
 58     tree[rt]=tree[rt<<1]+tree[rt<<1|1];
 59 }
 60 void update(int x,int val,lrrt){
 61     if(L==R){
 62         tree[rt]=val;
 63         return ;
 64     }
 65     imid;
 66     if(mid>=x) update(x,val,lson);
 67     else       update(x,val,rson);
 68     pushup(rt);
 69 }
 70 int query(int x,int y,lrrt){
 71     if(x<=L&&R<=y) return tree[rt];
 72     imid;
 73     int ans=0;
 74     if(mid>=x) ans+=query(x,y,lson);
 75     if(mid<y)  ans+=query(x,y,rson);
 76     return ans;
 77 }
 78 int getsum(int x,int y){
 79     int tx=top[x],ty=top[y],ans=0;
 80     while(tx!=ty){
 81         if(dep[tx]<dep[ty]){
 82             swap(tx,ty);
 83             swap(x,y);
 84         }
 85         ans+=query(sid[tx],sid[x],iall);
 86         x=fa[tx];
 87         tx=top[x];
 88     }
 89     if(x==y) return ans;
 90     if(dep[x]>dep[y]) swap(x,y);
 91     return ans+query(sid[son[x]],sid[y],iall);
 92 }
 93 int main(){
 94     int m,q,s;
 95     while(~scanf("%d%d%d",&m,&q,&s)){
 96         g.init();
 97         for(int i=1;i<m;i++){
 98             scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].w);
 99             g.add(e[i].u,e[i].v);
100             g.add(e[i].v,e[i].u);
101         }
102         n=fa[1]=dep[1]=num[0]=0;
103         dfs(1);
104         get(1,1);
105         mt(tree,0);
106         for(int i=1;i<m;i++){
107             if(dep[e[i].u]>dep[e[i].v]){
108                 swap(e[i].u,e[i].v);
109             }
110             update(sid[e[i].v],e[i].w,iall);
111         }
112         while(q--){
113             int op,x,y;
114             scanf("%d%d",&op,&x);
115             if(op){
116                 scanf("%d",&y);
117                 update(sid[e[x].v],y,iall);
118                 continue;
119             }
120             printf("%d\n",getsum(s,x));
121             s=x;
122         }
123     }
124     return 0;
125 }

View Code

Aladdin and the Return Journey http://lightoj.com/login_main.php?url=volume_showproblem.php?problem=1348

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 #define mt(a,b) memset(a,b,sizeof(a))
  5 #define lrrt int L,int R,int rt
  6 #define iall 1,n,1
  7 #define imid int mid=(L+R)>>1
  8 #define lson L,mid,rt<<1
  9 #define rson mid+1,R,rt<<1|1
 10 using namespace std;
 11 const int M=30010;
 12 struct G{
 13     struct E{
 14         int v,next;
 15     }e[M<<1];
 16     int le,head[M];
 17     void init(){
 18         le=0;
 19         mt(head,-1);
 20     }
 21     void add(int u,int v){
 22         e[le].v=v;
 23         e[le].next=head[u];
 24         head[u]=le++;
 25     }
 26 }g;
 27 int val[M],n,fa[M],dep[M],num[M],son[M],sid[M],top[M];
 28 void dfs(int u){
 29     num[u]=1;
 30     son[u]=0;
 31     for(int i=g.head[u];~i;i=g.e[i].next){
 32         int v=g.e[i].v;
 33         if(v!=fa[u]){
 34             fa[v]=u;
 35             dep[v]=dep[u]+1;
 36             dfs(v);
 37             if(num[son[u]]<num[v]) son[u]=v;
 38             num[u]+=num[v];
 39         }
 40     }
 41 }
 42 void get(int u,int Top){
 43     sid[u]=++n;
 44     top[u]=Top;
 45     if(son[u]) get(son[u],Top);
 46     for(int i=g.head[u];~i;i=g.e[i].next){
 47         int v=g.e[i].v;
 48         if(v!=fa[u]&&v!=son[u]){
 49             get(v,v);
 50         }
 51     }
 52 }
 53 int tree[M<<2];
 54 void pushup(int rt){
 55     tree[rt]=tree[rt<<1]+tree[rt<<1|1];
 56 }
 57 void update(int x,int val,lrrt){
 58     if(L==R){
 59         tree[rt]=val;
 60         return ;
 61     }
 62     imid;
 63     if(mid>=x) update(x,val,lson);
 64     else       update(x,val,rson);
 65     pushup(rt);
 66 }
 67 int query(int x,int y,lrrt){
 68     if(x<=L&&R<=y) return tree[rt];
 69     imid;
 70     int ans=0;
 71     if(mid>=x) ans+=query(x,y,lson);
 72     if(mid<y)  ans+=query(x,y,rson);
 73     return ans;
 74 }
 75 int getsum(int x,int y){
 76     int tx=top[x],ty=top[y],ans=0;
 77     while(tx!=ty){
 78         if(dep[tx]<dep[ty]){
 79             swap(tx,ty);
 80             swap(x,y);
 81         }
 82         ans+=query(sid[tx],sid[x],iall);
 83         x=fa[tx];
 84         tx=top[x];
 85     }
 86     if(dep[x]>dep[y]) swap(x,y);
 87     return ans+query(sid[x],sid[y],iall);
 88 }
 89 int main(){
 90     int t,m;
 91     while(~scanf("%d",&t)){
 92         int cas=1;
 93         while(t--){
 94             printf("Case %d:\n",cas++);
 95             scanf("%d",&m);
 96             for(int i=1;i<=m;i++){
 97                 scanf("%d",&val[i]);
 98             }
 99             g.init();
100             for(int i=1,u,v;i<m;i++){
101                 scanf("%d%d",&u,&v);
102                 g.add(u+1,v+1);
103                 g.add(v+1,u+1);
104             }
105             n=fa[1]=dep[1]=num[0]=0;
106             dfs(1);
107             get(1,1);
108             mt(tree,0);
109             for(int i=1;i<=m;i++){
110                 update(sid[i],val[i],iall);
111             }
112             scanf("%d",&m);
113             while(m--){
114                 int op,x,y;
115                 scanf("%d%d%d",&op,&x,&y);
116                 if(op) update(sid[x+1],y,iall);
117                 else printf("%d\n",getsum(x+1,y+1));
118             }
119         }
120     }
121     return 0;
122 }

View Code

两个待补

bzoj1146 树上第k大 LCA

bzoj2243 树上颜色统计

http://quartergeek.com/summary-of-heavy-light-decomposition/

end

posted on 2014-08-09 14:01 gaolzzxin 阅读(165) 评论(0) 编辑收藏举报