"BZOJ1305" [Cqoi2009]dance Dance

Description

There were n boys and n Girls at a dance. At the beginning of each song, all the boys and girls fit into the N-dance ballroom. Every boy will not dance with the same girl for two (or more) dance songs. There are some boys and girls who like each other, while others dislike each other (not "one-way Likes"). Each boy is willing to dance with the K-not-like girls at most, and each girl is willing to dance with the K-not-liked boys at most. Given the information that every pair of boys and girls love each other, how many dances can a ball have?

Input

The first line consists of two integers n and K. The following n rows contain n characters per line, where the J character of Line I is ' Y ' when and only if boy I and girl J love each other.

Output

Only one number, that is, the maximum number of dances.

Sample Input3 0
YYY
YYY
YYY
Sample Output3HINT

N<=50 k<=30

The boys and girls are x,ys to X-side, the capacity of the a,y to the meeting point, the capacity of AA can be two points, can be enumerated (anyway, only 30) boys x-->y with the side for K, girls y-->x with the side for K, boys like girls in the left side, vice versa in the right

1#include <cstdio>2#include <cstring>3#include <cmath>4#include <iostream>5 using namespacestd;6 Const intinf=100000000, n=1005;7 structee{intTo,next,f;} e[500001];8 inthead[n],q[n*2],dis[n],map[n][n];9 intS,t,n,m,cnt=1, ans,w,k,mx;Ten     One voidInsintUintVintf) { Ae[++cnt].to=v;e[cnt].f=f;e[cnt].next=head[u];head[u]=CNT; -e[++cnt].to=u;e[cnt].f=0; e[cnt].next=head[v];head[v]=CNT; - } the     - BOOLBFs () { -      for(intI=1; i<=t;i++) dis[i]=inf; -     intH=0, t=1, now; +q[1]=s;dis[s]=0; -      while(h!=t) { +now=q[++h]; A          for(intI=head[now];i;i=E[i].next) { at             intv=e[i].to; -             if(e[i].f&&dis[now]+1<Dis[v]) { -dis[v]=dis[now]+1; -                 if(v==t)return 1; -q[++t]=v; -             } in         } -     } to     if(Dis[t]==inf)return 0;return 1; + } -     the intDinic (intNowintf) { *     if(now==t)returnF; $     intrest=F;Panax Notoginseng      for(intI=head[now];i;i=E[i].next) { -         intv=e[i].to; the         if(e[i].f&&dis[v]==dis[now]+1&&rest) { +             intt=dinic (V,min (REST,E[I].F)); A             if(!t) dis[v]=0; thee[i].f-=T; +e[i^1].f+=T; -rest-=T; $         } $     } -     returnF-rest; - } the voidBuildintf) { -Cnt=1;WuyiMemset (Head,0,sizeof(head)); the      for(intI=1; i<=n;i++) ins (s,i,f); -      for(inti=n+1; i<=2*n;i++) ins (i,t,f); Wu      for(intI=1; i<=n;i++) Ins (i,i+2*n,k); -      for(inti=n+1; i<=2*n;i++) Ins (i+2*n,i,k); About      for(intI=1; i<=n;i++) $          for(intj=1; j<=n;j++){ -             if(Map[i][j]) ins (i,j+n,1); -             ElseINS (i+2*n,j+3*n,1); -         }  A } + intMain () { thescanf"%d%d",&n,&k); -t=4*n+1; $     Chars[ -]; the      for(intI=1; i<=n;i++){ thescanf"%s", s+1); the          for(intj=1; j<=n;j++) the             if(s[j]=='Y') map[i][j]=1; -     } in     intL=0, r= -; the      while(l<=R) the     { About         intMid= (l+r) >>1; the build (mid); theans=0; while(BFS ()) ans+=dinic (s,inf); the         if(Ans>=n*mid) {mx=mid;l=mid+1;} +         Elser=mid-1; -     } theprintf"%d", MX);Bayi}

"BZOJ1305" [Cqoi2009]dance Dance