HDU 3829 Maximum Independent set

Idea: It is clear that a certain child happy can be done, but at the same time it is possible to let other children unhappy, so each pair of such two children there is a "conflict", if there is "conflict" between the children to build a side, our problem is transformed into a binary map of the largest independent set. Specifically why is a binary chart, Bo Master also did not want to understand ...

1#include <iostream>2#include <cstring>3#include <cstdio>4 using namespacestd;5 6 Const intN =501;7 Const intM = N *N;8 Const intL = One;9 BOOLVisit[n];Ten intHead[n]; One intMark[n]; A intN, M, p, E; -  - structEdge the { -     intV, next; - } Edge[m]; -  + structHobby - { +     CharLike[l], dislike[l]; A } Hobby[n]; at  - voidInit () - { -E =0; -Memset (Head,-1,sizeof(head)); - } in  - voidAddedge (intUintv) to { +EDGE[E].V =v; -Edge[e].next =Head[u]; theHead[u] = e++; * } $ Panax Notoginseng intDfsintu) - { the      for(inti = Head[u]; I! =-1; i =edge[i].next) +     { A         intv =edge[i].v; the         if( !Visit[v]) +         { -VISIT[V] =true; $             if(Mark[v] = =-1||DFS (Mark[v])) $             { -MARK[V] =u; -Mark[u] =v; the                 return 1; -             }Wuyi         } the     } -     return 0; Wu } -  About inthunagry () $ { -memset (Mark,-1,sizeof(Mark)); -     intres =p; -      for(inti =1; I <= p; i++ ) A     { +         if(Mark[i]! =-1)Continue; thememset (Visit,0,sizeof(visit)); -Res-=DFS (i); $     } the     returnRes; the } the  the intMain () - { in      while(SCANF ("%d%d%d", &n, &m, &p)! =EOF) the     { the init (); About          for(inti =1; I <= p; i++ ) the         { thescanf"%s%s", Hobby[i].like, hobby[i].dislike); the              for(intj = i-1; J >0; j-- ) +             { -                 if(strcmp (hobby[i].like, hobby[j].dislike) = =0 the|| strcmp (hobby[j].like, hobby[i].dislike) = =0 )Bayi                 { the Addedge (i, j); the Addedge (J, i); -                 } -             } the         } theprintf"%d\n", Hunagry ()); the     } the     return 0; -}

HDU 3829 Maximum Independent set