Title Link: hdu_4918_query on the subtree
Test instructions
Give a tree of n points, each point has a weight, there are two operations, one is to change the weight of a point to v, and the other is to query the distance point you do not exceed the value of the point of D and.
Exercises
Here you can go to the film Bird God Blog.
The simple thing is to create two tree arrays for each center of gravity of the tree, then modify each point in the bit of the center of gravity, and query the bit in each center of gravity, and then let go of the Answer.
The complexity of each operation is log2n, the details of this problem is more, the specific look at the Code.
1#include <bits/stdc++.h>2 #defineF (i,a,b) for (int I=a;i<=b;i++)3 #definePB Push_back4 using namespacestd;5 Const intn=1e5+7;6 7 intn,q,g[n],nxt[n*2],v[n*2],ed,w[n],vis[n],id[n];8 intpool[ +*n],c_ed,pool_ed,sz[n],mi,mx[n],root;9 Charop[2];Ten one structnode a { - intrt,subrt,dis; - node () {} theNodeint_rt,int_subrt,int_dis): rt (_rt), subrt (_subrt), dis (_dis) {} - }tmp; -Vector<node>vt[n]; - + voidAdgintXintY) {v[++ed]=y,nxt[ed]=g[x],g[x]=ed;} - voidInit () {ed=c_ed=pool_ed=0; F (i,1, N) vt[i].clear (), vis[i]=g[i]=0;} +InlinevoidUpint&a,intB) {if(a<b) a=b;} a at structBIT - { - int*c,n; - voidInitintTot) {n=tot,c=pool+pool_ed,pool_ed+=tot+1; F (i,0, N) c[i]=0;} -InlinevoidAddintXintC) { while(x<=n) c[x]+=c,x+=x&-x;} -InlineintAskintXintan=0) in { - if(x>n) x=n; to while(x>0) an+=c[x],x-=x&-x; + returnan ; - } the}tr[n*2]; * $ voidGet_rt (intUintFaintNum)Panax Notoginseng { -sz[u]=1, mx[u]=0; the for(intI=g[u];i;i=nxt[i]) + if(!vis[v[i]]&&v[i]!=Fa) a { the Get_rt (v[i],u,num); +sz[u]+=sz[v[i]],up (mx[u],sz[v[i]); - } $Up (mx[u],num-sz[u]); $ if(mx[u]<mi) Root=u,mi=mx[u]; - } - the voidDelintUintFaintRtintsubrt,intdis=1)//place each point of the subtree in the corresponding center of gravity - {Wuyi VT[U].PB (node (rt,subrt,dis)); theTr[rt].add (dis+1, w[u]); -Tr[subrt].add (dis+1, w[u]); wu for(intI=g[u];i;i=nxt[i]) - if(v[i]!=fa&&!vis[v[i]]) aboutDel (v[i],u,rt,subrt,dis+1); $ } - - voidInit_tree (intu=1,intnum=N) - { aMi=N,get_rt (u,u,num); + intrt=root,rt_id=++c_ed; theTr[c_ed].init (sz[u]+2); -vis[rt]=1, VT[RT].PB (node (c_ed,0,0)); $Tr[c_ed].add (1, w[rt]); theGet_rt (rt,rt,num);//new calculation of sz size the for(intI=g[rt];i;i=nxt[i]) the if(!vis[v[i]]) the { -Tr[++c_ed].init (sz[v[i]]+2); in del (v[i],v[i],rt_id,c_ed); the } the for(intI=g[rt];i;i=nxt[i]) about if(!vis[v[i]]) the Init_tree (v[i],sz[v[i]); the } the + intMain () - { the while(~SCANF ("%d%d",&n,&q))Bayi { the Init (); theF (i,1, N) scanf ("%d", w+i); -F (i,1, n-1) - { the intx, y; thescanf"%d%d",&x,&y); the ADG (x, y), ADG (y,x); the } - Init_tree (); the while(q--) the { the intu,v;94scanf"%s%d%d",op,&u,&v); the if(op[0]=='!') the { the intSize=vt[u].size (), d=v-w[u];98F (i,0, size-1) about { -tmp=vt[u][i];101Tr[tmp.rt].add (tmp.dis+1, d);//dis+1 Remove the bug that the distance is 0 timeout on bit102 if(tmp.subrt) Tr[tmp.subrt].add (tmp.dis+1, d);103 }104w[u]+=d; the}Else106 {107 intd=v,ans=0, size=vt[u].size ();108F (i,0, size-1)109 { thetmp=vt[u][i];111Ans+=tr[tmp.rt].ask (d-tmp.dis+1); the if(tmp.subrt) Ans-=tr[tmp.subrt].ask (d-tmp.dis+1);113 } theprintf"%d\n", ans); the } the }117 }118 return 0;119}
View Code
Hdu_4918_query on the subtree (tree partition + Tree Array)