UVa Q544

//UVa Q544
#include <bits/stdc++.h>
using namespace std;

struct stat{
    int V, W;
    bool operator<(const stat &x)const{return W < x.W;}
};

vector<stat> v[200];
bool vis[200];

int32_t main(){
    int n,m,x, cnt = 0;
    while(cin >> n >> m){
        if(n == 0 && m == 0)break;
        for(int i = 0; i < n; ++i){
            v[i].clear();
            vis[i] = 0;
        }
        string s1, s2;
        map<string, int> cite;
        map<string, int>::iterator it;
        int k = 0;
        for(int i = 0; i < m; ++i){
            cin >> s1 >> s2 >> x;
            it = cite.find(s1);
            if(it == cite.end())cite[s1] = k++;
            it = cite.find(s2);
            if(it == cite.end())cite[s2] = k++;
            stat in = {.V = cite[s2], .W = x};
            v[cite[s1]].emplace_back(in);
            in = {.V = cite[s1], .W = x};
            v[cite[s2]].emplace_back(in);
        }
        cin >> s1 >> s2;
        int start = cite[s1];
        int ended = cite[s2];
        priority_queue<stat> pq;
        stat tmd = {.V=start, .W=1000000000};
        pq.push(tmd);
        int ans = -1;
        while(!pq.empty() && ans == -1){
            tmd = pq.top();
            pq.pop();
            vis[tmd.V] = 1;
            //cout << tmd.V << ' ' << tmd.W<<endl;
            if(tmd.V == ended){
                ans = tmd.W;
                break;
            };
            for(unsigned i = 0; i < v[tmd.V].size(); ++i){
                if(!vis[v[tmd.V][i].V]){
                    stat in = v[tmd.V][i];
                    in.W = min(in.W, tmd.W);
                    pq.push(in);
                }
            }
        }
        cout << "Scenario #" << ++cnt << '\n';
        cout << ans << " tons\n\n";
    }
    return 0 ;
}