# bzoj3275: Number

#include<cstdio>
#include<iostream>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<cmath>
using namespace std;
const int inf=999999999;
const double eps=1e-8;

struct node
{
int x,y,c,next,other;
}a[410000];int len,last[310000];
void ins(int x,int y,int c)
{
int k1,k2;

len++;k1=len;
a[len].x=x;a[len].y=y;a[len].c=c;
a[len].next=last[x];last[x]=len;

len++;k2=len;
a[len].x=y;a[len].y=x;a[len].c=0;
a[len].next=last[y];last[y]=len;

a[k1].other=k2;
a[k2].other=k1;
}

int st,ed,h[310000],list[310000];
bool bt_h()
{
memset(h,0,sizeof(h));h[st]=1;
{
for(int k=last[x];k;k=a[k].next)
{
int y=a[k].y;
if(a[k].c>0&&h[y]==0)
{
h[y]=h[x]+1;
list[tail]=y;
tail++;
}
}
}
if(h[ed]==0)return false;
return true;
}
int findflow(int x,int f)
{
if(x==ed)return f;
int s=0;
for(int k=last[x];k;k=a[k].next)
{
int y=a[k].y;
if(a[k].c>0&&h[y]==h[x]+1&&s<f)
{
int t=findflow(y,min(a[k].c,f-s));
s+=t;a[k].c-=t;a[a[k].other].c+=t;
}
}
if(s==0)h[x]=0;
return s;
}

int ak[310000];
int gcd(int a,int b)
{
if(a==0)return b;
return gcd(b%a,a);
}
int main()
{
int n,sum=0;
scanf("%d",&n);
st=n+1,ed=n+2;
for(int i=1;i<=n;i++)
{
scanf("%d",&ak[i]);sum+=ak[i];
if(ak[i]%2==1)ins(st,i,ak[i]);
else           ins(i,ed,ak[i]);
for(int j=1;j<i;j++)
{
double c=sqrt(double(ak[i]*ak[i])+double(ak[j]*ak[j]));
if(gcd(ak[i],ak[j])==1&&fabs(c-double(int(c)))<=eps)
if(ak[i]%2==1)
ins(i,j,inf);
else
ins(j,i,inf);
}
}//composition

int ans=0;
while(bt_h()==true)
{
ans+=findflow(st,999999999);
}
printf("%d\n",sum-ans);
return 0;
}

pain and happy in the cruel world.
posted @ 2018-02-27 21:25  AKCqhzdy  阅读(111)  评论(0编辑  收藏  举报