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 = 1005;
const int maxm = 1000005;
struct Edge{
    int u,v,next;
}edge[ maxm ];
int cnt ,head[ maxn ];
void init(){
    cnt = 0;
    memset( head,-1,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=1;i<=n;i++ ){
            scanf("%d%d",&val[i],&cost[i]);
            fa[ i ] = i;
        }
        init();
        memset( dp,0,sizeof( dp ) );
        memset( root,0,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 = 1;
        for( int i=1;i<=n;i++ ){
            int x = find( i );
            if( root[x]==0 ){
                root[x] = r++;
            }
            addedge( root[x],i );
        }
        for( int i=1;i<r;i++ ){
            for( int j=Max;j>=0;j-- ){
                for( int k=head[i];k!=-1;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
",dp[Max]);
    }
    return 0;
}