CSU1326+背包+并查集

先预处理出有多少个任务即可

 #include<stdio.h>
 #include<stdlib.h>
 #include<string.h>
 #include<algorithm>
 #include<math.h>
 using namespace std;
 const int maxn = ;
 const int maxm = ;
 struct Edge{
     int u,v,next;
 }edge[ maxm ];
 int cnt ,head[ maxn ];
 void init(){
     cnt = ;
     memset( head,-,sizeof( head ) );
 }
 void addedge( int a,int b ){
     edge[ cnt ].u = a;
     edge[ cnt ].v = b;
     edge[ cnt ].next = head[ a ];
     head[ a ] = cnt ++;
 }
 int fa[ maxn ],root[ maxn ],dp[ maxn ];
 int val[ maxn ],cost[ maxn ];
 int find( int x ){
     if( x==fa[x] ) return x;
     else return fa[x] = find( fa[x] );
 }
 int main(){
     int n,Max,k;
     while( ~scanf("%d%d%d",&n,&Max,&k) ){
         for( int i=;i<=n;i++ ){
             scanf("%d%d",&val[i],&cost[i]);
             fa[ i ] = i;
         }
         init();
         memset( dp,,sizeof( dp ) );
         memset( root,,sizeof( root ) );
         while( k-- ){
             int a,b;
             scanf("%d%d",&a,&b);
             int x = find(a);
             int y = find(b);
             if( fa[x]!=y ){
                 fa[x] = y;
             }
         }
         int r = ;
         for( int i=;i<=n;i++ ){
             int x = find( i );
             if( root[x]== ){
                 root[x] = r++;
             }
             addedge( root[x],i );
         }
         for( int i=;i<r;i++ ){
             for( int j=Max;j>=;j-- ){
                 for( int k=head[i];k!=-;k=edge[k].next ){
                     int nxt = edge[k].v;
                     if( j>=cost[nxt] ){
                         dp[j] = max( dp[j],dp[j-cost[nxt]]+val[nxt] );
                     }
                 }
             }
         }
         printf("%d\n",dp[Max]);
     }
     return ;
 }