OJ-Problems-Source/HDOJ/3879_autoAC.cpp

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#include<iostream>
#include<cstring>
#include<cstdio>
#define MAXN 60000
#define INF 1e8
#define min(a,b) (a<b?a:b)
#define max(a,b) (a>b?a:b)
using namespace std;
struct edge
{
int u,v,w,next;
}E[400050];
int head[MAXN],ecnt;
int gap[MAXN],cur[MAXN],pre[MAXN],dis[MAXN];
int l,r,mid;
int N,M,scr,sink,vn,num;
void Insert(int u,int v,int w)
{
E[ecnt].u=u;
E[ecnt].v=v;
E[ecnt].w=w;
E[ecnt].next=head[u];
head[u]=ecnt++;
E[ecnt].u=v;
E[ecnt].v=u;
E[ecnt].w=0;
E[ecnt].next=head[v];
head[v]=ecnt++;
}
int Sap(int s,int t,int n)
{
int ans=0,aug=INF;
int i,v,u=pre[s]=s;
for(i=0;i<=n;i++)
{
cur[i]=head[i];
dis[i]=gap[i]=0;
}
gap[s]=n;
bool flag;
while(dis[s]<n)
{
flag=false;
for(int &j=cur[u];j!=-1;j=E[j].next)
{
v=E[j].v;
if(E[j].w>0&&dis[u]==dis[v]+1)
{
flag=true;
aug=min(aug,E[j].w);
pre[v]=u;
u=v;
if(u==t)
{
ans+=aug;
while(u!=s)
{
u=pre[u];
E[cur[u]].w-=aug;
E[cur[u]^1].w+=aug;
}
aug=INF;
}
break;
}
}
if(flag) continue;
int mindis=n;
for(i=head[u];i!=-1;i=E[i].next)
{
v=E[i].v;
if(E[i].w>0&&dis[v]<mindis)
{
mindis=dis[v];
cur[u]=i;
}
}
if((--gap[dis[u]])==0) break;
gap[dis[u]=mindis+1]++;
u=pre[u];
}
return ans;
}
int n,m;
int main()
{
while(scanf("%d%d",&n,&m)!=EOF)
{
memset(head,-1,sizeof(head));ecnt=0;
scr=0;sink=n+m+1;vn=sink+1;
for(int i=1;i<=n;i++)
{
int v;
scanf("%d",&v);
Insert(i,sink,v);
}
int sum=0;
for(int i=1;i<=m;i++)
{
int a,b,v;
scanf("%d%d%d",&a,&b,&v);
Insert(scr,i+n,v);
Insert(i+n,a,INF);
Insert(i+n,b,INF);
sum+=v;
}
printf("%d\n",sum-Sap(scr,sink,vn));
}
return 0;
}