Create 1511_aszxqw.cpp

From http://blog.csdn.net/wuyanyi/article/details/7286014

POJ/1511_aszxqw.cpp

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+//36412K	1829MS
+#include<iostream>
+#include<vector>
+#include<string>
+#include<queue>
+#include<algorithm>
+#define llong long long
+#define Abs(a) ((a)>0?(a):-(a))
+#define Mod(a,b) (((a)-1+(b))%(b)+1)
+using namespace std;
+const int N=1000005;
+const int inf=1e10;
+int n,m;
+int a[N][3];
+struct
+{
+	int w,v,next;
+}edge[N];
+int edgehead[N];
+llong d[N];
+bool vis[N];
+int k;
+void addedge(int u,int v,int w)
+{
+	edge[k].v=v;
+	edge[k].w=w;
+	edge[k].next=edgehead[u];
+	edgehead[u]=k++;
+}
+struct cmp//注意priority_queue的cmp写的和sort里面的cmp的区别，前者是struct，后者是函数，而且比较大小的关系刚好是相反的。
+{
+	bool operator()(const int a,const int b)
+	{
+		return d[a]>d[b];
+	}
+};
+llong dijstra()
+{
+	memset(vis,0,sizeof(vis));
+	priority_queue<int,vector<int>,cmp> que;
+	for(int i=2;i<=n;i++)
+		d[i]=inf;
+	d[1]=0;
+	que.push(1);
+	while(!que.empty())
+	{
+		int u=que.top();
+		vis[u]=true;
+		que.pop();
+		for(int i=edgehead[u];i;i=edge[i].next)//遍历节点u的每条出去的边
+		{
+			int v=edge[i].v;
+			int w=edge[i].w;
+			if(!vis[v]&&d[v]>d[u]+w)//如果是可松弛点即加入优先队列，d值越小越优先。
+			{
+				d[v]=d[u]+w;
+				que.push(v);
+			}
+		}
+	}
+	llong ans=0;
+	for(int i=1;i<=n;i++)
+		ans+=d[i];
+	return ans;
+}
+int main()
+{
+	int cases;
+	scanf("%d",&cases);
+	while(cases--)
+	{
+		k=1;
+		memset(edgehead,0,sizeof(edgehead));
+		memset(edge,0,sizeof(edge));
+		scanf("%d%d",&n,&m);
+		for(int i=1;i<=m;i++)
+		{
+			scanf("%d%d%d",a[i],a[i]+1,a[i]+2);
+			addedge(a[i][0],a[i][1],a[i][2]);
+		}
+		llong ans=dijstra();
+		k=1;//将图的边反向之后再来一遍
+		memset(edgehead,0,sizeof(edgehead));
+		memset(edge,0,sizeof(edge));
+		for(int i=1;i<=m;i++)
+		{
+			addedge(a[i][1],a[i][0],a[i][2]);
+		}
+		ans+=dijstra();
+		printf("%lld\n",ans);
+	}
+	return 0;
+}