Contest2037 - CSU Monthly 2013 Oct (problem D ：CX and girls)

【题解】：

最短路径问题，保证距离最短的同时，学妹权值最大，哈哈

【code】：

 #include<iostream>
 #include<queue>
 #include<stdio.h>
 #include<string.h>
 #include<stdlib.h>

 #define N 50005
 #define INF 100000000
 using namespace std;

 struct Edge
 {
     int to;
     int next;
     int w;
     int num;
 }edge[N<<];

 struct Nod
 {
    int u;
    int dis;
    int num;
 }now,temp;

 bool operator< (Nod a,Nod b)
 {
     if(a.dis!=b.dis)
         return a.dis>b.dis;
     return a.num<b.num;
 }

 int weight[N],head[N],visit[N];
 int dis[N];
 int ans[N];

 void init(int n)
 {
     int i;
     for(i=;i<=n;i++)
     {
         visit[i] = ;
         dis[i] = INF;
         head[i] = -;
         ans[i]=-;
     }
 }

 void Dijkstra(int s)
 {
     int i,v;
     dis[s] = ;
     ans[s] = weight[s];
     priority_queue<Nod> p_q;
     temp.dis = ;
     temp.u = s;
     temp.num = weight[s];
     p_q.push(temp);
     while(!p_q.empty())
     {
         temp = p_q.top();
         p_q.pop();
         if(visit[temp.u])  continue;
         visit[temp.u] = ;
         for(i=head[temp.u];i!=-;i=edge[i].next)
         {
             v = edge[i].to;
             if(!visit[v])
             {
                 if(dis[v]>dis[temp.u]+edge[i].w||(dis[v]!=INF&&dis[v]==dis[temp.u]+edge[i].w&&ans[v]<ans[temp.u]+weight[v]))
                 {
                     dis[v] = dis[temp.u]+edge[i].w;
                     ans[v] = ans[temp.u]+weight[v];
                     now.u = v;
                     now.dis = dis[v];
                     now.num = ans[v];

                     p_q.push(now);
                 }
             }
         }
     }
 }

 int main()
 {
     int m,n;
     while(~scanf("%d%d",&n,&m))
     {
         int i;
         for(i=;i<n;i++)    scanf("%d",weight+i);
         int id = ;
         init(n);
         int a,b,c;
         for(i=;i<m;i++)
         {
             scanf("%d%d%d",&a,&b,&c);
             a--,b--;
             edge[id].to = b;
             edge[id].w = c;
             edge[id].next = head[a];
             head[a] = id++;  //将边 a --> b保存

             edge[id].to = a;
             edge[id].w = c;
             edge[id].next = head[b];
             head[b] = id++;  //将边 b --> a保存
         }
         Dijkstra();
         printf("%d\n",ans[n-]);
     }
     return ;
 }