"Bzoj" "2502" cleaning the snow track

Network flow/upper and lower bound network flow

The least viable flow below the bounds ...

I am a SB, running the network stream is to run from the virtual source 0. Instead of s ...

Orz Hzwer

1 /**************************************************************2 problem:25023 User:tunix4 language:c++5 result:accepted6 time:3080 Ms7 memory:10652 KB8 ****************************************************************/9  Ten //Bzoj 2502 One#include <vector> A#include <cstdio> -#include <cstdlib> -#include <cstring> the#include <iostream> -#include <algorithm> - #defineRep (i,n) for (int i=0;i<n;++i) - #defineF (i,j,n) for (int i=j;i<=n;++i) + #defineD (i,j,n) for (int i=j;i>=n;--i) - using namespacestd; + intGetint () { A     intv=0, sign=1;CharCh=GetChar (); at      while(ch<'0'|| Ch>'9') {if(ch=='-') sign=-1; Ch=GetChar ();} -      while(ch>='0'&&ch<='9') {v=v*Ten+ch-'0'; Ch=GetChar ();} -     returnv*Sign ; - } -typedefLong LongLL; - Const intn=100010, m=500010, inf=~0u>>2; in /*******************tamplate********************/ - intN,m,ans; to structedge{intto,v;}; + structnet{ - Edge E[m]; the     inthead[n],next[m],cnt; *     voidInsintXintYintz) { $e[++cnt]=(Edge) {y,z};Panax NotoginsengNEXT[CNT]=HEAD[X]; head[x]=CNT; -     } the     voidAddintXintYintz) { +Ins (x, y, z); Ins (y,x,0); A     } the     intS,t,d[n],cur[n],q[m]; +     BOOLMklevel () { -         intL=0, r=-1; $F (I,0, T) d[i]=-1; $d[0]=0; q[++r]=0; -          while(l<=R) { -             intx=q[l++]; the              for(intI=head[x];i;i=Next[i]) -                 if(E[I].V && d[e[i].to]==-1){Wuyid[e[i].to]=d[x]+1; theq[++r]=e[i].to; -                 } Wu         } -         returnd[t]!=-1; About     } $     intDfsintXinta) { -         if(x==t)returnA; -         intflow=0; -          for(int&i=cur[x];i && flow<a;i=Next[i]) A             if(E[I].V && d[e[i].to]==d[x]+1){ +                 intF=dfs (E[i].to,min (e[i].v,a-flow)); thee[i].v-=F; -e[i^1].v+=F; $flow+=F; the             } the         if(!flow) d[x]=-1; the         returnflow; the     } -     voidDinic () { in          while(Mklevel ()) { theF (I,0, T) cur[i]=Head[i]; theAns+=dfs (0, INF); About         } the     } the     int inch[N]; the     voidinit () { +N=getint (); Cnt=1; m=0; -F (I,1, N) { the             intx=getint (), y;BayiF (J,1, X) { theY=getint (); m++; theAdd (i,n+2*m-1, INF); -Add (n+2*m,y,inf); -             } the         } thes=n+m+m+1; t=s+1; ans=0; theF (I,1, M) { theAdd (n+2*i-1, n+2*i,inf); -             inch[n+2*i-1]--;inch[n+2*i]++; the         } theF (I,1, N) Add (s,i,inf); theF (i,n+1, n+m+m)94             if(inch[i]>0) Add (0Iinch[i]); the             ElseAdd (i,t,-inch[i]); the          for(intI=1;; i++){ theAdd0S1);98 dinic (); About             if(ans==m) {printf ("%d\n", i); Break;} -         }101     }102 }g1;103 intMain () {104 #ifndef Online_judge theFreopen ("Input.txt","R", stdin);106 //freopen ("Output.txt", "w", stdout);107     #endif108 g1.init ();109     return 0; the}

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"Bzoj" "2502" cleaning the snow track