"UVA10765" Doves and Bombs (BCC cut-off points after the number of unicom blocks)

Topic:

Test instructions

Gave a unicom without a map, now ask to remove a point, will make the diagram into a few unicom block?

The output is divided by the number of small, if equal, the output label from small to large. Output of M.

Analysis:

The number of connected blocks after the BCC cut point, Tarjan algorithm.

The number of Unicom blocks is accumulated when a low[y]>=dfn[x] is found, and the last one can be added.

The code is as follows:

1#include <cstdio>2#include <cstdlib>3#include <cstring>4#include <iostream>5#include <algorithm>6 using namespacestd;7 #defineMAXN 100108 9 intn,m;Ten intFIRST[MAXN],LOW[MAXN],DFN[MAXN],FA[MAXN],SON[MAXN]; One intCUT[MAXN]; A intCNT; -  - structnode the { -     intX,y,next; - }; -Node t[maxn*Ten],ANS[MAXN]; + intLen; -  + intMymin (intXintY) {returnX<y?x:y;} A  at voidInsintXinty) - { -t[++len].x=x;t[len].y=y; -t[len].next=first[x];first[x]=Len; - } -  in BOOLCMP (node X,node y) {return(x.x==y.x)? (X.Y&LT;Y.Y):(x.x>y.x);} -  to voidFfind (intXintf) + { -dfn[x]=low[x]=++CNT; thefa[x]=F; *      for(intI=first[x];i;i=t[i].next)if(t[i].y!=f) $     {Panax Notoginseng         inty=t[i].y; -         if(dfn[y]==0) the         { + Ffind (y,x); Ason[x]++; thelow[x]=mymin (Low[x],low[y]); +             if(Low[y]>=dfn[x]) cut[x]++; -         } $         Elselow[x]=mymin (Low[x],dfn[y]); $     } - } -  the intMain () - {Wuyi      while(1) the     { -scanf"%d%d",&n,&m); Wu         if(n==0&&m==0) Break; -len=0; cnt=0; Aboutmemset (First,0,sizeof(first)); $          while(1) -         { -             intb; -scanf"%d%d",&a,&b); A             if(a==-1&&b==-1) Break; +a++;b++; the ins (A, B); ins (b,a); -         } $memset (DFN,0,sizeof(DFN)); thememset (Cut,0,sizeof(cut)); theMemset (son,0,sizeof(son)); theFfind (1,0); ans[1].y=0; the         if(son[1]>1) ans[1].x=son[1]; -         Elseans[1].x=1; in          for(intI=2; i<=n;i++) the         { theans[i].y=i-1; Aboutans[i].x=cut[i]+1; the         } theSort (ans+1, ans+1+n,cmp); the          for(intI=1; i<=m;i++) printf ("%d%d\n", ans[i].y,ans[i].x); +printf"\ n"); -     } the     return 0;Bayi}

[UVA10765]

2016-03-17 13:43:40

"UVA10765" Doves and Bombs (BCC cut-off points after the number of unicom blocks)