Codeforces 741B Arpa's weak amphitheater and Mehrdad's valuable Hoses

#include <cstdio>
#include <vector>
#include <algorithm>
#include <cstring>
#define rep(i,n) for(int i=1;i<=n;i++)
using namespace std;
const int N=1010;
int dp[N],f[N],n,m,x,y,size,w[N],b[N];
vector<int> v[N];
int sf(int x){return f[x]==x?x:f[x]=sf(f[x]);}
int main(){  
    while(~scanf("%d%d%d",&n,&m,&size)){  
        rep(i,n)f[i]=i,v[i].clear();
        rep(i,n)scanf("%d\n",&w[i]);  
        rep(i,n)scanf("%d\n",&b[i]);
        rep(i,m){scanf("%d%d",&x,&y);f[sf(x)]=sf(y);}  
        rep(i,n)v[sf(i)].push_back(i);  
        memset(dp,0,sizeof(dp));  
        rep(i,n)if(sf(i)==i){  
            for(int j=size;j>=0;j--){  
                int W=0,B=0;  
                for(int k=0;k<v[i].size();k++){  
                    W+=w[v[i][k]]; B+=b[v[i][k]];  
                    if(j>=w[v[i][k]])dp[j]=max(dp[j],dp[j-w[v[i][k]]]+b[v[i][k]]);  
                }if(j>=W)dp[j]=max(dp[j],dp[j-W]+B);  
            }  
        }printf("%d\n",dp[size]);  
    }return 0;  
}