#include <iostream>
#include <map>
#include <utility>
#include <vector>
#include <assert.h>
using namespace std;

#define int long long

using int64 = long long;
using P = pair<int, int>;   // (棟, 階)

const int maxn = 300000;
const int64 inf = (1LL << 60);

map<int, int64> table[maxn];
map<int, vector<int>> G[maxn];

signed main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    int64 N, M, K, S, T;
    cin >> N >> M >> K >> S >> T;

    assert(1 <= N and N <= 200000);
    assert(0 <= M and M <= 200000);
    assert(1 <= K and K <= 1e9);
    assert(1 <= S and S <= K);
    assert(1 <= T and T <= K);

    for (int i = 0; i < M; i++) {
        int a, b, c;
        cin >> a >> b >> c;

        assert(1 <= a and a <= N - 1);
        assert(1 <= b and b <= K);
        assert(1 <= c and c <= K);

        a--;
        
        G[a][b].push_back(c);
        table[a][b] = inf;
        table[a + 1][c] = inf;
    }

    if (N == 1 and M == 0) {
        cout << abs(S - T) << endl;
        return 0;
    }

    for (auto& mp : table[N - 1]) mp.second = abs(T - mp.first);
    for (int i = N - 1; i >= 0; i--) {
        int64 val = inf;
        for (auto& p : table[i]) {
            for (int to : G[i][p.first]) {
                p.second = min(p.second, table[i + 1][to]);
            }
            p.second = min(p.second, val + p.first);
            val = min(val, p.second - p.first);
        }

        val = inf;
        for (auto it = table[i].rbegin(); it != table[i].rend(); it++) {
            it->second = min(it->second, val - it->first);
            val = min(val, it->second + it->first);
        }
    }

    int64 ans = inf;
    for (auto& mp : table[0]) ans = min(ans, mp.second + abs(S - mp.first));

    if (ans >= inf / 2) cout << -1 << endl;
    else cout << ans << endl;

    return 0;
}