并查集——搭配购买

搭配购买

解：用并查集将需要搭配购买的云朵合并到同一集合中，同时要维护各个集合的价钱和价值。然后枚举并查集中的每个集合，对所有集合跑一遍01背包即可。

#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for(int i = a;i<n;i++)
#define per(i,a,n) for(int i = n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
#define yes cout<<"YES"<<'\n';
#define no cout<<"NO"<<'\n';
#define endl '\n';
typedef vector<int> VI;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll MOD=1000000007;
int rnd(int x) {return mrand() % x;}
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;};
ll lcm(int a,int b){return a*b/gcd(a,b);};

const int N=10010;
int n,m,w;
int p[N],c[N],d[N];
int f[N],v[N],g[N];
int cnt;

int findd(int x){
	return p[x]==x?x:p[x]=findd(p[x]);
}

void unionn(int x,int y){
	x=findd(x),y=findd(y);
	if(x==y) return;
	p[x]=y;
	c[y]+=c[x];
	d[y]+=d[x];
}

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>n>>m>>w;
	rep(i,1,n+1){
		p[i]=i;
		cin>>c[i]>>d[i];
	}
	int ans=0;
	rep(i,0,m){
		int a,b;
		cin>>a>>b;
		unionn(a,b);
	}
	rep(i,1,n+1){
		if(p[i]==i) v[cnt]=c[i],g[cnt++]=d[i];
	}
	rep(i,0,cnt){
		per(j,v[i],w+1){
			f[j]=max(f[j],f[j-v[i]]+g[i]);
		}
	}
	cout<<f[w];
	return 0;
}