#include <bits/stdc++.h>

using namespace std;

#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)
#define SZ(a) int(a.size())
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;

const int N = 1 << 10;
const LL LINF = 1e18;

vector<PII> g[N];
bool used[N];
VI toposort;
LL dp[N][N];
int idx[N];

template<typename T>
void updMin(T& a, T b)
{
	a = min(a, b);
}

void dfs(int v)
{
	used[v] = true;
	for (auto [to, w] : g[v])
	{
		if (!used[to])
			dfs(to);
	}
	toposort.PB(v);
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);	
	int n, m;
	cin >> n >> m;
	FOR(i, 0, m)
	{
		int u, v, w;
		cin >> u >> v >> w;
		u--;
		v--;
		g[u].PB({v, w});
		g[v].PB({u, w});
	}
	int s1, t1, s2, t2;
	cin >> s1 >> t1 >> s2 >> t2;
	s1--;
	t1--;
	s2--;
	t2--;
	dfs(s1);
	if (!used[s2])
		dfs(s2);
	reverse(ALL(toposort));
	int k = SZ(toposort);
	fill(idx, idx + n, -1);
	FOR(i, 0, k)
		idx[toposort[i]] = i;
	for (int v : toposort)
		cerr << v << " ";
	cerr << endl;
	if (idx[t2] == -1 || idx[t2] == -1)
	{
		cout << "NIE\n";
		return 0;
	}
	FOR(i, 0, k)
		FOR(j, 0, k)
			dp[i][j] = LINF;
	dp[idx[s1]][idx[s2]] = 0;
	FOR(i, 0, k)
	{
		int u = toposort[i];
		FOR(j, 0, k)
		{
			int v = toposort[j];
			if (i < j || v == t2)
			{
				for (auto [to, w] : g[u])
				{
					updMin(dp[idx[to]][j], dp[i][j] + w);
				}
			}
			if (i > j || u == t1)
			{
				for (auto [to, w] : g[v])
				{
					updMin(dp[i][idx[to]], dp[i][j] + w);
				}
			}
		}
	}
	LL ans = dp[idx[t1]][idx[t2]];
	if (ans == LINF)
		cout << "NIE\n";
	else
		cout << ans << "\n";
	return 0;
}