> #include <stdio.h>
> #include <stdlib.h>
> #define max 10005
> typedef struct villageinf
> {	int a;
> 	int b;
> 	int dis;
> }village;
> int main(void)
> {	village road[max];
> 	int i,j,n,k,largersum;
> 	int node[max];
> 	int num[max];
> 	memset(road,0,sizeof(road));
> 	memset(num,0,sizeof(num));
> 	memset(node,0,sizeof(node));
> 	n=0;
> 	while(scanf("%d%d%d",&road[n].a,&road[n].b,&road[n].dis)!=EOF) 
> 	{	if(road[n].a==0&&road[n].b==0) break;
> 		num[road[n].a]++;
> 		num[road[n].b]++;
> 		n++;
> 	}
> 	/*for(i=0;i<n;i++)
> 		printf("%d %d %d\n",road[i].a,road[i].b,road[i].dis);*/
> 	k=0;largersum=0;
> 	//printf("%d\n",n);
> 	while(k<=n-2)
> 	{	for(i=0;i<n;i++)
> 		{	if(num[road[i].a]==1&&num[road[i].b]>0)
> 			{	num[road[i].a]=0;
> 				if(largersum<node[road[i].b]+road[i].dis+node[road[i].a])
> 					largersum=node[road[i].b]+road[i].dis+node[road[i].a];
> 				if(node[road[i].b]<road[i].dis+node[road[i].a])
> 					node[road[i].b]=road[i].dis+node[road[i].a];
> 				road[i].dis=0;
> 				num[road[i].b]--;
> 				k++;
> 				//printf("%d,%d,%d,%d\n",road[i].a,node[road[i].b],road[i].b,k);
> 				if(k==n-1)
> 					break;
> 			}
> 			else if(num[road[i].b]==1&&num[road[i].a]>0)
> 			{	num[road[i].b]=0;
> 				if(largersum<node[road[i].b]+road[i].dis+node[road[i].a])
> 					largersum=node[road[i].b]+road[i].dis+node[road[i].a];
> 				if(node[road[i].a]<road[i].dis+node[road[i].b])
> 					node[road[i].a]=road[i].dis+node[road[i].b];
> 				road[i].dis=0;
> 				num[road[i].a]--;
> 				k++;
> 				//printf("%d,%d,%d,%d\n",road[i].b,node[road[i].a],road[i].a,k);
> 				if(k==n-1)
> 					break;
> 			}
> 		}
> 	}
> 	for(i=0;i<n;i++)
> 		if(road[i].dis>0)
> 		{	if(largersum<=node[road[i].a]+node[road[i].b]+road[i].dis)
> 				printf("%d\n",node[road[i].a]+node[road[i].b]+road[i].dis);
> 			else printf("%d\n",largersum);
> 			break;
> 		}
> 	return 0;
> }
>