UVALive 7338 （树链剖分+线段树）

  1 #include <map>
  2 #include <set>
  3 #include <stack>
  4 #include <queue>
  5 #include <cmath>
  6 #include <ctime>
  7 #include <string>
  8 #include <vector>
  9 #include <cstdio>
 10 #include <cstdlib>
 11 #include <cstring>
 12 #include <cassert>
 13 #include <iostream>
 14 #include <algorithm>
 15 #pragma comment(linker,"/STACK:102400000,102400000")
 16 using namespace std;
 17 
 18 #define V 10008             
 19 #define E 200008    
 20 #define LL long long
 21 #define lson l,m,rt<<1
 22 #define rson m+1,r,rt<<1|1 
 23 #define clr(x,v) memset(x,v,sizeof(x));
 24 #define bitcnt(x) __builtin_popcount(x)
 25 #define rep(x,y,z) for (int x=y;x<=z;x++)
 26 #define repd(x,y,z) for (int x=y;x>=z;x--)
 27 const int mo  = 1000000007;
 28 const int inf = 0x3f3f3f3f;
 29 const int INF = 2000000000;
 30 /**************************************************************************/ 
 31 int n,m,sum,cnt;
 32 int lt[V],dep[V],son[V],w[V],rk[V],fa[V],top[V],size[V];
 33 int a[E],b[E];
 34 
 35 struct line{
 36     int u,v,w,nt;
 37     line(int u=0,int v=0,int w=0,int nt=0):u(u),v(v),w(w),nt(nt){}
 38 }eg[E],EG[E];
 39 void add(int u,int v,int w){
 40     eg[++sum]=line(u,v,w,lt[u]); lt[u]=sum;
 41 }
 42 void dfs_1(int u){
 43     dep[u]=dep[fa[u]]+1; size[u]=1; son[u]=0; 
 44     for (int i=lt[u];i;i=eg[i].nt){
 45         int v=eg[i].v;
 46         if (v==fa[u]) continue;
 47         fa[v]=u;
 48         dfs_1(v);
 49         if (size[v]>size[son[u]]) son[u]=v;
 50         size[u]+=size[v];
 51     }
 52 }
 53 void dfs_2(int u,int tp){
 54     top[u]=tp; w[u]=++cnt; rk[cnt]=u;
 55     if (son[u]) dfs_2(son[u],tp);
 56     for (int i=lt[u];i;i=eg[i].nt){
 57         int v=eg[i].v;
 58         if (v==fa[u]||v==son[u]) continue;
 59         dfs_2(v,v);
 60     }
 61 }
 62 struct Segment_Tree{
 63     int mx[V<<2],lazy[V<<2];
 64     inline void pushup(int rt){
 65         mx[rt]=max(mx[rt<<1],mx[rt<<1|1]);
 66     }
 67     inline void pushdown(int rt){
 68         if (lazy[rt]!=-INF){
 69             lazy[rt<<1]=max(lazy[rt<<1],lazy[rt]);
 70             lazy[rt<<1|1]=max(lazy[rt<<1|1],lazy[rt]);
 71             mx[rt<<1]=max(mx[rt<<1],lazy[rt]);
 72             mx[rt<<1|1]=max(mx[rt<<1|1],lazy[rt]);
 73             lazy[rt]=-INF;
 74         }
 75     }
 76     void build(int l,int r,int rt){
 77         mx[rt]=-INF; lazy[rt]=-INF;
 78         if (l==r) return;
 79         int m=(l+r)>>1;
 80         build(lson);
 81         build(rson);
 82         pushup(rt);
 83     }
 84     void update(int L,int R,int val,int l,int r,int rt){
 85         if (L<=l && r<=R){
 86             lazy[rt]=max(val,lazy[rt]);
 87             mx[rt]=max(mx[rt],val);
 88             return;
 89         }
 90         pushdown(rt);
 91         int m=(l+r)>>1;
 92         if (L <= m) update(L,R,val,lson);
 93         if (m <  R) update(L,R,val,rson);
 94         pushup(rt);
 95     }
 96     int query(int L,int R,int l,int r,int rt){
 97         if (L<=l && r<=R){
 98             return mx[rt];
 99         }
100         pushdown(rt);
101         int m=(l+r)>>1;
102         int res=-INF;
103         if (L <= m) res=max(res,query(L,R,lson));
104         if (m <  R) res=max(res,query(L,R,rson));
105         return res;
106     }
107 }T1,T2;
108 int find(int x,int y){
109     int res=-INF;
110     while (top[x]!=top[y]){
111         if (dep[top[x]]<dep[top[y]]) swap(x,y);
112         res=max(res,T1.query(w[top[x]],w[x],1,n,1));
113         x=fa[top[x]];
114     }
115     if (dep[x]>dep[y]) swap(x,y);
116     res=max(res,T1.query(w[x]+1,w[y],1,n,1));
117     return res;
118 }
119 void change(int x,int y,int val){
120     while (top[x]!=top[y]){
121         if (dep[top[x]]<dep[top[y]]) swap(x,y);
122         T2.update(w[top[x]],w[x],val,1,n,1);
123         x=fa[top[x]];
124     }
125     if (dep[x]>dep[y]) swap(x,y);
126     T2.update(w[x]+1,w[y],val,1,n,1);
127 }
128 int main(){
129     int T,cas=0;
130     scanf("%d",&T);
131     while (T--){
132         clr(lt,0); sum=1; cnt=0;
133 
134         scanf("%d%d",&n,&m);
135         for (int i=1;i<n;i++){
136             int u,v,w;
137             scanf("%d%d%d",&u,&v,&w);
138             add(u,v,w); add(v,u,w);        
139             EG[i]=line(u,v,w);
140         }
141         for (int i=n;i<=m;i++){
142             int u,v,w;
143             scanf("%d%d%d",&u,&v,&w);        
144             EG[i]=line(u,v,w);
145         }
146         dfs_1(1);
147         dfs_2(1,1);
148         T1.build(1,n,1);
149         T2.build(1,n,1);
150         for (int i=1;i<n;i++){
151             if (dep[EG[i].u]>dep[EG[i].v]) swap(EG[i].u,EG[i].v);
152             T1.update(w[EG[i].v],w[EG[i].v],EG[i].w,1,n,1);
153         }
154         for (int i=n;i<=m;i++){
155             int tmp=find(EG[i].u,EG[i].v);
156             b[i]=tmp==-INF?-1:EG[i].w-tmp;
157             change(EG[i].u,EG[i].v,-EG[i].w);
158         }
159         for (int i=1;i<n;i++){
160             int tmp=T2.query(w[EG[i].v],w[EG[i].v],1,n,1);
161             a[i]=tmp==-INF?-1:-tmp-EG[i].w;
162         }
163         LL res=0;
164         for (int i=1;i<n;i++) res=res+1ll*i*a[i]+1ll*i*i*-1;
165         for (int i=n;i<=m;i++) res=res+1ll*i*-1+1ll*i*i*b[i];
166         
167         printf("Case %d: %lld\n",++cas,res );
168     }
169 }