int Dijkstra(int START,int END)
{
priority_queue<City,vector<City>,CMP> QUE;
vector<int> Path(MAXN,INF);
Path[START]=0;
City temp;
temp.set(START,0);
QUE.push(temp);
while(!QUE.empty())
{
int Ups=QUE.top().LCity;
if(Ups==END) return QUE.top().Cost;
QUE.pop();
for(unsigned i=0;i<Graph[Ups].size();i++){
int tCity=Graph[Ups][i].LCity;
int tCost=Graph[Ups][i].Cost;
if(tCost+Path[Ups]<Path[tCity]){
Path[tCity]=tCost+Path[Ups];
temp.set(tCity,Path[tCity]);
QUE.push(temp);
}
}
}
return -1;
}
int main()
{
int m;
while(scanf("%d%d",&n,&m),n||m){
Graph.clear();
Graph.resize(n+1);
for(int i=0;i<m;i++){
int c1,c2,cost;
scanf("%d%d%d",&c1,&c2,&cost);
City temp;
temp.set(c2,cost);
Graph[c1].push_back(temp);
temp.set(c1,cost);
Graph[c2].push_back(temp);
}
printf("%d\n",Dijkstra(1,n));
}
}
bool Cities::create_city(const std::string &_str,
Countries &_countries,
City &_city){
auto country_sm_name = 0;
auto city_name = 1;
auto latitude = 5;
auto longitude = 6;
std::vector<std::string> tokens;
StringUtils::split(_str, tokens, ',');
if (tokens.size() >= (longitude + 1)){
auto country_id = _countries.add_country(tokens[country_sm_name], tokens[country_sm_name]);
_city.set(tokens[city_name],
boost::lexical_cast<float>(tokens[latitude]),
boost::lexical_cast<float>(tokens[longitude]),
country_id);
return true;
}
return false;
}