#include <bits/stdc++.h>
using namespace std;
using i64 = int64_t;
using vi = vector<i64>;
using vvi = vector<vi>;

int main() {
    int n, m, s, g;
    cin >> n >> m >> s >> g;
    vvi d(n, vi(n, 1e9));
    for (int i = 0; i < n; i++) {
        d[i][i] = 0;
    }
    for (int i = 0; i < m; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        d[a][b] = c;
        d[b][a] = c;
    }

    vvi dd(d);

    for (int k = 0; k < n; k++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
            }
        }
    }

    int mindist = d[s][g];
    cout << s;
    int pre = s;
    while (1) {
        for (int i = 0; i < n; i++) {
            if (i == pre) continue;
            if (dd[pre][i] + d[i][g] == mindist) {
                cout << " " << i;
                mindist -= dd[pre][i];
                pre = i;
                break;
            }
        }
        if (mindist == 0) break;
    }
    cout << endl;
}