https://ac.nowcoder.com/acm/contest/373/C

题解：并查集

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=100000+10;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int t,n,m,k,q;
ll ans,cnt,flag,temp;
ll a[N],v[N],b[N];
char str;
int find(int x){
    if(v[x]==x)return x;
    return find(v[x]);
}
void add(int x,int y){
    int tx=find(x);
    int ty=find(y);
    if(tx!=ty){
        v[tx]=ty;
        a[ty]+=a[tx];
    }
}

int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    scanf("%d%d",&n,&m);
    //scanf("%d",&t);
    //while(t--){}
    for(int i=1;i<=n;i++){
        scanf("%lld",&a[i]);
        v[i]=i;
    }
    for(int i=1;i<=n;i++){
        scanf("%lld",&k);
        add(i,k);
    }
    for(int i=1;i<=n;i++){
        if(v[i]==i){
            b[++cnt]=a[i];
        }
    }
    sort(b+1,b+cnt+1,greater<int>());
    for(int i=1;i<=m;i++){
        ans+=b[i];
    }
    cout << ans << endl;
    //cout << "Hello world!" << endl;
    return 0;
}