#include <cstdio>
#include <iostream>
#include <fstream>
#include <cmath>
#include <algorithm>
#include <ctime>
#include <cctype>
#include <cstdlib>
#include <cassert>
#include <functional>
#include <iomanip>
#include <string>
#include <cstring>
#include <map>
#include <set>
#include <vector>
#include <queue>

using namespace std;

int s, f;

vector <pair <int, int> > g[3000];

queue < pair<int, int> > bfs;

int used[3000];

int am[5000];
int bm[5000];
int rm[5000];

string d[3000];

int ans = 1e9;

string sum1(const string &a1, const string &b1)
{
        string a = a1;
        string b = b1;

        int flag = 0;

        string s1 = "";

        while(a.size() != b.size())
        {
                if(a.size() > b.size())
                        b = '0' + b;
                else
                        a = '0' + a;
        }

        for(int i = 0; i <= a.size(); i++)
                s1 += '0';

        for(int i = max(a.size(), b.size()) - 1; i >= 0; i--)
        {
                int a1, b1;

                a1 = int(a[i]) - int('0');
                b1 = int(b[i]) - int('0');

                s1[i + 1] = char( ((a1 + b1 + flag) % 10) + '0' );

                //cerr << a1 << " " << b1 << " " << s1[i + 1] << endl;

                flag = (a1 + b1 + flag) / 10;

        }

        s1[0] = char(flag + '0');

        //cerr << a << "+" << b << "=" << s1 << endl;
        return s1;
}

string sum(const string &a1, const string &b1)
{
   string a = a1;
    string b = b1;

    //длинное сложение
    cerr << a << endl << b << endl;

    for(int i = 0; i < 3000; i++)
    {
        am[i] = 0;
        bm[i] = 0;
        rm[i] = 0;
    }

    int u1 = 1;
    int u2 = 1;

    if(a.size() > b.size())
    {
        int r = a.size() - b.size();

        u2 += r;
    }

    if(a.size() < b.size())
    {
        int r = b.size() - a.size();

        u1 += r;
    }

    //cerr << u1 << " " << u2 << endl;

    for(int i = u1; i < u1 + a.size(); i++)
        am[i] = a[i - u1] - '0';

    for(int i = u2; i < u2 + b.size(); i++)
        bm[i] = b[i - u2] - '0';

    for(int i = 0; i < 3000; i++)
        rm[i] = am[i] + bm[i];

    for(int i = 3000; i > 0; i--)
    {
        if(rm[i] >= 10)
        {
            rm[i] -= 10;
            rm[i - 1]++;
        }
    }

    string answer = "";

    for(int i = 0; i < u1 + a.size(); i++)
        answer.push_back( char( int(rm[i]) + int('0') ) );

    cerr << answer << endl;

    return answer;
}

string rec(int x)
{
    if(d[x] == "")
    {

        if(x == s)
        {
            return("1");
        }

        string  res = "00000000";

        for(int i = 0; i < g[x].size(); i++)
        {
            if(used[g[x][i].first] == used[x] - g[x][i].second)
            {
                //cerr << "(" << res << " "  << rec(g[x][i].first) << ")" << endl;
                res = sum(res, rec(g[x][i].first) );
            }
        }

        d[x] = res;
        return res;
    }
    else
        return(d[x]);
}
int main ()
{


    int n, m;

    cin >> n >> m;

    for(int i = 0; i < 2000; i++)
        used[i] = 1e8;

    for(int i = 0; i < m; i++)
    {
        int a, b, c;
        scanf("%d%d%d", &a, &b, &c);

        g[a].push_back(make_pair(b, c));
        g[b].push_back(make_pair(a, c));
    }

    cin >> s >> f;

    bfs.push( make_pair(s, 0) );
    used[s] = 0;

    while(!bfs.empty())
    {
        pair<int, int> t;

        t = bfs.front();

        if(t.first == f)
        {
            ans = min(ans, t.second);
        }

        bfs.pop();

        for(int i = 0; i < g[t.first].size(); i++)
        {
            if(used[ g[t.first][i].first ] > t.second + g[t.first][i].second)
            {
                bfs.push(make_pair(g[t.first][i].first, g[t.first][i].second + t.second));

                used[g[t.first][i].first] = g[t.first][i].second + t.second;
            }
        }

    }
    //for(int i = 0; i < 2000; i++)
    //  used[i] = 0;

    if(ans == 1e9)
    {
        cout << 0;
        return 0;
    }

    int flag = 0;
    //return 0;

    string answer = rec(f);

    for(int i = 0; i < answer.size(); i++)
    {
        if(flag == 0 && answer[i] != '0')
        {
            flag = 1;
        }

        if(flag == 1)
            cout << answer[i];
    }

    //cout << rec(f);

    return 0;
}