poj 1511 Invitation Cards

#include<iostream>
#include<cstdio>
#include<queue>
#define inf 1000000005
using namespace std;
struct node
{
int y,cost,next;
}edge[1000005];
int dist[1000005],visit[1000005];
int a[1000005],b[1000005],c[1000005],h[1000005];
int n,m;
__int64 ans;
queue<int> q;
__int64 SPFA()
{
__int64 ans1=0;
int i;
int x;
for(i=1;i<=n;i++)
{
dist[i]=inf;
visit[i]=0;
}
q.push(1);
visit[1]=1;dist[1]=0;
while(!q.empty())
{
x=q.front();
q.pop();
for(i=h[x];i;i=edge[i].next)
{
if(dist[edge[i].y]>dist[x]+edge[i].cost)
{
dist[edge[i].y]=dist[x]+edge[i].cost;
if(!visit[edge[i].y])
{
visit[edge[i].y]=1;q.push(edge[i].y);
}
}
}
}
for(i=1;i<=n;i++)
ans1+=dist[i];
return ans1;
}
int main()
{
int t,i,p;
scanf("%d",&t);
while(t--)
{
scanf("%d %d",&n,&m);
ans=0;p=0;
memset(h,0,sizeof(h));
for(i=0;i<m;i++)
{
scanf("%d %d %d",&a[i],&b[i],&c[i]);
edge[++p].y=b[i];
edge[p].cost=c[i];
edge[p].next=h[a[i]];
h[a[i]]=p;
}
ans+=SPFA();
p=0;
memset(h,0,sizeof(h));
for(i=0;i<m;i++)
{
edge[++p].y=a[i];
edge[p].cost=c[i];
edge[p].next=h[b[i]];
h[b[i]]=p;
}
ans+=SPFA();
printf("%I64d\n",ans);
}
return 0;
}