BZOJ1119: [POI2009]SLO

 1 #include<cstdio>
 2 #include<cstdlib>
 3 #include<cmath>
 4 #include<cstring>
 5 #include<algorithm>
 6 #include<iostream>
 7 #include<vector>
 8 #include<map>
 9 #include<set>
10 #include<queue>
11 #include<string>
12 #define inf 1000000000
13 #define maxn 1000000+1000
14 #define maxm 500+100
15 #define eps 1e-10
16 #define ll long long
17 #define pa pair<int,int>
18 #define for0(i,n) for(int i=0;i<=(n);i++)
19 #define for1(i,n) for(int i=1;i<=(n);i++)
20 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
21 using namespace std;
22 inline int read()
23 {
24     int x=0,f=1;char ch=getchar();
25     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
26     while(ch>=‘0‘&&ch<=‘9‘){x=10*x+ch-‘0‘;ch=getchar();}
27     return x*f;
28 }
29 ll n,mi=inf,cs=0,a[maxn],b[maxn],c[maxn],d[maxn],w[maxn];
30 bool check[maxn];
31 int main()
32 {
33     freopen("input.txt","r",stdin);
34     freopen("output.txt","w",stdout);
35     n=read(); 
36     for1(i,n)w[i]=read(),mi=min(w[i],mi);
37     for1(i,n)d[i]=a[i]=read();
38     for1(i,n)b[i]=read();
39     for1(i,n)c[b[i]]=i;
40     for1(i,n)a[i]=c[a[i]];
41     ll ans=0;
42     for1(i,n)
43      if(!check[i])
44       {
45           ll j=i,len=0,tmp=inf,sum=0;
46           while(!check[j])
47           {
48            check[j]=1;
49            tmp=min(tmp,w[d[j]]);
50            sum+=w[d[j]];
51            len++;
52            j=a[j];
53           } 
54         ans+=sum+min((len-2)*tmp,mi*(len+1)+tmp);  
55       }
56     cout<<ans<<endl;  
57     return 0;
58 }