#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int, int>
#define pb push_back
#define rep(a, b, c, d) for(int a=b; a<=c; a+=d)
#define INF LLONG_MAX
const int N = 1e5 + 5;
int n, m, cnt, head[N];
struct edge {
	int next;
	int to;
	int len;
} e[N];
struct node {
	int d;
	int v;
	bool operator<(const node &x) const {
		return d > x.d;
	}
};
void add(int u, int v, int w) {
	++ cnt;
	e[cnt].to = v;
	e[cnt].len = w;
	e[cnt].next = head[u];
	head[u] = cnt;
}
queue<node> q;
bitset<N> vis;
int dis[N];
void dijkstra(int s) {
	rep(i, 1, n, 1)
		dis[i] = INF;
	dis[s] = 0;
	q.push({0, s});
	while(!q.empty()) {
		node f = q.front();
		q.pop();
		int x = f.v;
		if(vis[x])
			continue;
		vis[x] = 1;
		for(int i = head[x]; i; i = e[i].next) {
			int v = e[i].to;
			if(dis[v] > dis[x] + e[i].len) {
				dis[v] = dis[x] + e[i].len;
				q.push({dis[v], v});
			}
		}
	}
}
signed main () {
	cin >> n >> m;
	rep(i, 1, m, 1) {
		int u, v, w;
		cin >> u >> v >> w;
		int u2 = (u > n ? u - n : u + n);
		int v2 = (v > n ? v - n : v + n);
		add(u, v2, w);
		add(v, u2, w);
	}
	int s, t;
	cin >> s >> t;
	s = (s > n ? s - n : s + n);
	dijkstra(s);
	dis[t] == INF ? cout << "I have no idea how to solve it." : cout << dis[t];
	return 0;
}