Rivers ioi2005 Tree DP

To tell the truth, after writing this question, very want to vomit a mouthful of blood out, to show my mood is bad;

The topic is very simple, the tree-shaped DP, normally do 30 minutes, obstinately did for several hours, really sad.

The puzzle is not written, just spit a groove, online no backpack write DP, all is left son right brother writing, can not control a bit, uncomfortable ah.

Code:

1#include <iostream>2#include <cstdio>3#include <cstring>4 using namespacestd;5 #defineLL Long Long6 intn,k;7 Const intmaxn= About;8 ConstLL inf=3000000000LL;9 structnode{Ten     inty,next,v; One }E[MAXN]; A intlinkk[maxn],len=0, w[maxn],d[maxn][maxn],siz[maxn],q[maxn],tail=0, FA[MAXN],RU[MAXN],VIS[MAXN]; - intRead () { -     intx=0;CharCh=getchar ();BOOLflag=0; the      while(ch<'0'|| Ch>'9'){if(ch=='-') flag=1; ch=GetChar ();} -      while(ch<='9'&&ch>='0') {x=x*Ten+ch-'0'; ch=GetChar ();} -     returnflag?-x:x; - } + voidInsertintXintYintv) { -e[++len].y=y; +e[len].v=v; Ae[len].next=Linkk[x]; atlinkk[x]=Len; - } - voidPrintintx) {printf ("%d\n", x);} - voidPrintintXintY) {printf ("%d%d\n", x, y);} - voidinit () { -     inty,v; inN=read (), k=read (); -memset (D,Ten,sizeof(d)); to      for(intI=1; i<=n;i++){ +W[i]=read (), Y=read (), v=read (); - Insert (i,y,v); insert (y,i,v); thed[i][y]=v,d[y][i]=v; *     } $     Panax Notoginseng } - voidfindd () { the      for(intI=1; i<=n;i++) d[i][i]=0; +      for(intk=0; k<=n;k++) A          for(intI=0; i<=n;i++) the              for(intj=0; j<=n;j++) +                 if(D[i][k]+d[k][j]<d[i][j]) d[i][j]=d[i][k]+D[k][j]; - } $LL f[ the][ -][ the]; $ voidDfsintXintf) { -siz[x]=1; -fa[x]=F; the      for(intI=linkk[x];i;i=E[i].next) { -         if(e[i].y==f)Continue;Wuyi DFS (e[i].y,x); thesiz[x]+=SIZ[E[I].Y]; -ru[x]++; Wu     } -     if(siz[x]==1) q[++tail]=x; About } $ voidWork () { -memset (f,-1,sizeof(f)); - findd (); -Dfs0,0); A      for(intHead=1; head<=tail;head++){ +         intx=Q[head]; theru[fa[x]]--; -         if(ru[fa[x]]==0) q[++tail]=Fa[x]; $LL g[ About]; the          for(intk=0; k<=siz[x]&&k<=k;k++){ the              for(intPREV=FA[X];p rev!=-1;p rev=Fa[prev]) { the                  the                  for(intp=0;p <=k;p++) g[p]=0; -                  for(intI=linkk[x];i;i=E[i].next) { in                     if(E[i].y==fa[x])Continue; theLL minn=inf; the                      for(intj=k;j>=0; j--){ Aboutminn=inf; the                          for(intL=0; l<=siz[e[i].y]&&l<=j;l++) theMinn=min (minn,g[j-l]+F[e[i].y][l][prev]); theg[j]=Minn; +                     } -                 } theLL ans=g[k]+w[x]*D[prev][x];Bayi                  for(intp=0;p <=k;p++) g[p]=0; the                  for(intI=linkk[x];i;i=E[i].next) { the                     if(E[i].y==fa[x])Continue; -LL minn=inf; -                      for(intj=k-1; j>=0; j--){ theminn=inf; the                          for(intL=0; l<=siz[e[i].y]&&l<=j;l++) theMinn=min (minn,g[j-l]+f[e[i].y][l][x]); theg[j]=Minn; -                     } the                 } theF[x][k][prev]=min (ans,k-1<0? inf:g[k-1]); the                 if(!prev) Break;94             } the         } the     } thecout<<f[0][k][0]<<Endl;98 } About intMain () { -Freopen ("1.in","R", stdin);101Freopen ("1.out","W", stdout);102 init ();103 Work ();104}

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Rivers ioi2005 Tree DP