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（果然不加当前弧优化要略快一点）

  1 /**************************************************************
  2     Problem: 3158
  3     User: Tunix
  4     Language: C++
  5     Result: Accepted
  6     Time:196 ms
  7     Memory:13028 kb
  8 ****************************************************************/
  9
 10 //BZOJ 3158
 11 #include<cmath>
 12 #include<vector>
 13 #include<cstdio>
 14 #include<cstring>
 15 #include<cstdlib>
 16 #include<iostream>
 17 #include<algorithm>
 18 #define rep(i,n) for(int i=0;i<n;++i)
 19 #define F(i,j,n) for(int i=j;i<=n;++i)
 20 #define D(i,j,n) for(int i=j;i>=n;--i)
 21 #define pb push_back
 22 using namespace std;
 23 inline int getint(){
 24     int v=0,sign=1; char ch=getchar();
 25     while(ch<‘0‘||ch>‘9‘){ if (ch==‘-‘) sign=-1; ch=getchar();}
 26     while(ch>=‘0‘&&ch<=‘9‘){ v=v*10+ch-‘0‘; ch=getchar();}
 27     return v*sign;
 28 }
 29 const int N=1100,M=1000000,INF=~0u>>2;
 30 typedef long long LL;
 31 /******************tamplate*********************/
 32 int n,m,tot,ans,a[N],b[N];
 33 struct edge{int to,v;};
 34 int gcd(int a,int b){return b ? gcd(b,a%b) : a;}
 35 bool judge(LL a,LL b){
 36     LL s=a*a+b*b;
 37     LL q=sqrt(s);
 38     if (q*q!=s) return 0;
 39     if (gcd(a,b)!=1) return 0;
 40     return 1;
 41 }
 42 struct Net{
 43     edge E[M];
 44     int head[N],next[M],cnt;
 45     void ins(int x,int y,int v){
 46         E[++cnt]=(edge){y,v};
 47         next[cnt]=head[x]; head[x]=cnt;
 48     }
 49     void add(int x,int y,int v){
 50         ins(x,y,v); ins(y,x,0);
 51     }
 52     int s,t,d[N],Q[N];
 53     void init(){
 54         n=getint(); cnt=1;
 55         tot=ans=0;
 56         s=0; t=n+1;
 57         F(i,1,n) a[i]=getint();
 58         F(i,1,n){
 59             b[i]=getint();tot+=b[i];
 60             if (a[i]&1) add(s,i,b[i]);
 61             else add(i,t,b[i]);
 62         }
 63         F(i,1,n) if (a[i]&1)
 64             F(j,1,n) if((a[j]&1)==0)
 65                 if (judge(a[i],a[j])) add(i,j,INF);
 66     }
 67     bool mklevel(){
 68         memset(d,-1,sizeof d);
 69         d[s]=0;
 70         int l=0,r=-1;
 71         Q[++r]=s;
 72         while(l<=r){
 73             int x=Q[l++];
 74             for(int i=head[x];i;i=next[i])
 75                 if (d[E[i].to]==-1 && E[i].v){
 76                     d[E[i].to]=d[x]+1;
 77                     Q[++r]=E[i].to;
 78                 }
 79         }
 80         return d[t]!=-1;
 81     }
 82     int dfs(int x,int a){
 83         if (x==t) return a;
 84         int flow=0;
 85         for(int i=head[x];i && flow<a;i=next[i])
 86             if (E[i].v && d[E[i].to]==d[x]+1){
 87                 int f=dfs(E[i].to,min(a-flow,E[i].v));
 88                 E[i].v-=f;
 89                 E[i^1].v+=f;
 90                 flow+=f;
 91             }
 92         if (!flow) d[x]=-1;
 93         return flow;
 94     }
 95     void Dinic(){
 96         while(mklevel())
 97             ans+=dfs(s,INF);
 98     }
 99 }G1;
100
101 int main(){
102 #ifndef ONLINE_JUDGE
103     freopen("3158.in","r",stdin);
104     freopen("3158.out","w",stdout);
105 #endif
106     G1.init(); G1.Dinic();
107     printf("%d\n",tot-ans);
108     return 0;
109 }