poj 1125

最短路径问题，我用的是临接表来存储各个边的信息，用优先队列的dijkstra算法

#include <iostream>
#include <queue>
#include <vector>
using namespace std;
const int maxn=101;
const int INF=2<<20;
struct edge 
{
	int po,w;
	edge * next;
};
struct node
{
	edge * first;
}head[maxn];
typedef pair<int,int>pii;
priority_queue<pii,vector<pii>,greater<pii> >q;
int n,per,minx;
void dijkstra()
{
	int low[maxn],i,j,visit[maxn];
	minx=INF;
	for(i=1;i<=n;i++)
	{
		int max=-1;
		int tot=0;
		for(j=1;j<=n;j++)
		{
			low[j]=j==i?0:INF;
			visit[j]=0;
		}
		q.push(make_pair(low[i],i));
		while(!q.empty())
		{
			pii u=q.top();
			q.pop();
			int x=u.second;
			if(visit[x]) continue;
			visit[x]=1;
			tot++;
			if(low[x]>max)
				max=low[x];
			edge * tem=head[x].first;
			while(tem!=NULL)
			{
				if(low[tem->po]>(low[x]+tem->w))
				{
					low[tem->po]=low[x]+tem->w;
					q.push(make_pair(low[tem->po],tem->po));
				}
				tem=tem->next;
			}
		}
		if(tot==n)
		{
		if(max<minx)
		{
			minx=max;
			per=i;
		}
		}
	}
}
int main()
{
	while(cin>>n&&n!=0)
	{
		int i,t,e,w;
		for(i=1;i<=n;i++) head[i].first=NULL;
		edge * tem;
		for(i=1;i<=n;i++)
		{
			cin>>t;
			while(t--)
			{
				cin>>e>>w;
				tem=new edge;
				tem->po=e;
				tem->w=w;
				tem->next=head[i].first;
				head[i].first=tem;
			}
		}
		dijkstra();
		cout<<per<<" "<<minx<<endl;
	}
	return 0;
}