#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];

unsigned long long d[3000];


int ans = 1e9;

int m[3000][3000];

/*
string sum(const string &a, const string &b)
{
    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;
}
*/
unsigned long long rec(int x)
{
    if(d[x] == 0)
    {

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

        unsigned long long res = 0;

        for(int i = 0; i < g[x].size(); i++)
        {
            if(used[g[x][i].first] == used[x] - g[x][i].second)
            {
                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] = 1e9;

    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;
    }

    cout << rec(f);

    return 0;
}