USACO 2009 Dec cow toll paths 过路费

#include<cstdio>
#include<cstdlib>
const int maxn=300;
const int maxm=10002;
const int inf=maxn*100000;
int c[maxn],id[maxn],d[maxn][maxn];
int ans[maxm],src[maxm],dst[maxm];
int n,m,q,u,v,w,t,i,j;
int max(int a,int b)
{
	return a>b?a:b;
}
int main()
{
	freopen("toll.in","r",stdin);
	freopen("toll.out","w",stdout);
	scanf("%d%d%d",&n,&m,&q);
	for(u=1;u<=n;u++)
	{
		scanf("%d",&c[u]);
		id[u]=u;
	}
	for(int i=1;i<=n;i++)
	{
		for(int j=i+1;j<=n;j++)
		{
			if(c[id[i]]>c[id[j]])
			{
				u=id[i];
				id[i]=id[j];
				id[j]=u;
			}
		}
	}
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=n;j++)
		{
			d[i][j]=inf;
		}
	}
	for(i=1;i<=m;i++)
	{
		scanf("%d%d%d",&u,&v,&t);
		if(d[u][v]>t)
		{
			d[u][v]=t;
			d[v][u]=t;
		}
	}
	for(i=1;i<=q;i++)
	{
		scanf("%d%d",&u,&v);
		src[i]=u;
		dst[i]=v;
		ans[i]=d[u][v]+max(c[u],c[v]);
	}
	for(i=1;i<=n;i++)
	{
		w=id[i];
		for(u=1;u<=n;u++)
		{
			for(v=1;v<=n;v++)
			{
				if(d[u][v]>d[u][w]+d[w][v])
				{
					d[u][v]=d[u][w]+d[w][v];
				}
			}
		}
		for(j=1;j<=q;j++)
		{
			u=src[j];
			v=dst[j];
			t=d[u][v]+max(max(c[u],c[v]),c[w]);
			if(ans[j]>t)
				ans[j]=t;
		}
	}
	for(i=1;i<=q;i++)
	{
		printf("%d\n",ans[i]);
	}
	fclose(stdin);
	fclose(stdout);
	return 0;
}