P1179: [APIO2009]ATM

Pinch point +SPFA Shortest path, because there is no ring, so direct SPFA.

1 ConstMaxe=1000001;2 type3Node=Record4 F,t:longint;5 end;6 varN,m,s,i,j,ans,cnt,num,u,x,dgr:longint;7h,he,dfn,low,q,d,v,va,bl:array[0.. Maxe] of Longint;8b,bi:array[0.. Maxe] of node;9f:array[0.. maxe* -] of Longint;Tenp:array[0.. Maxe] of Boolean; One function min (a,b:longint): Longint; A begin -   ifA>b then exit (b)Elseexit (a); - end; the procedure Insert (u,v:longint); - begin -With Bi[i] Do - begin +f:=He[u]; -t:=v; + end; Ahe[u]:=i; at end; - procedure Reinsert (u,v:longint); - begin - Inc (CNT); -With B[CNT] Do - begin inf:=H[u]; -t:=v; to end; +h[u]:=CNT; - end; the procedure Readd; * varI,e,v:longint; $ beginPanax Notoginsengcnt:=0; -    fori:=1to n Do the begin +e:=He[i]; A        whileE<>0  Do the begin +v:=bi[e].t; -           ifBl[i]<>Bl[v] Then reinsert (Bl[i],bl[v]); $e:=bi[e].f; $ end; - end; - end; the procedure Tarjan (x:longint); - varE,t,j:longint;Wuyi begin the Inc (DGR); Inc (NUM); -p[x]:=true; F[num]:=x; DFN[X]:=DGR; low[x]:=dgr; Wue:=He[x]; -    whileE<>0  Do About begin $t:=bi[e].t; -       ifdfn[t]=0 Then - begin - Tarjan (t); A           ifLow[x]>low[t] Then low[x]:=Low[t]; + End the       Else if(P[t]) and (Dfn[t]<low[x]) then low[x]:=Dfn[t]; -e:=bi[e].f; $ end; the   ifdfn[x]=Low[x] Then the begin thej:=0; Inc (CNT); the        whileJ<>x Do - begin inj:=F[num]; the Dec (num); thep[j]:=false; Aboutbl[j]:=CNT; the           //Writeln (J, ", CNT); the Inc (V[cnt],va[j]); the end; + end; - end; the procedure SPFA;Bayi varE,t,now,l,r:longint; the begin theFillchar (P,sizeof(p),true); -Fillchar (D,sizeof(d),0); -l:=1; r:=1; f[1]:=bl[s]; p[bl[s]]:=false; D[bl[s]]:=v[bl[s]];//Writeln (V[bl[s]); the    whileL<=r Do the begin thenow:=F[l]; thee:=H[now]; -        whileE<>0  Do the begin thet:=b[e].t; the           //if T=1 then Writeln (' X ', now, ', v[t]);94           ifd[t]<d[now]+V[t] Then the begin thed[t]:=d[now]+V[t]; the               ifP[t] Then98 begin Aboutp[t]:=false; - Inc (R);101f[r]:=T;102 end;103 end;104e:=b[e].f; the end;106 Inc (L);107p[now]:=true;108 end;109 end; the begin111 readln (n,m); the    fori:=1to M Do113 begin the readln (u,x); the Insert (u,x); the end;117    fori:=1to n Doreadln (Va[i]);118Fillchar (P,sizeof(p),false);119    fori:=1to n Do ifdfn[i]=0Then Tarjan (i); - readln (s,m);121 Readd;122   //For i:=1 to 4 do Writeln (V[i]);123 SPFA;124    fori:=1to M Do the begin126 read (u);127       ifD[bl[u]]>ans then ans:=D[bl[u]]; - end;129 writeln (ans); theEnd.

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P1179: [APIO2009]ATM