#include <bits/stdc++.h>

using namespace std;
typedef pair<int, int> pii;
typedef long long ll;

map<pii, ll> dp;
vector<pii> G[200010];

int main(void) {
  int n, m, k, s, t;
  cin >> n >> m >> k >> s >> t;
  for (int i = 0; i < m; i++) {
    int a, b, c;
    cin >> a >> b >> c;
    G[a].push_back(pii(b, c));
  }
  for (int i = 1; i <= n; i++) {
    sort(G[i].begin(), G[i].end());
  }


  for (int i = n; i >= 1; i--) {
    if (i == n) {
      for (int j = 0; j < G[i - 1].size(); j++) {
        dp[pii(i, G[i - 1][j].second)] = abs(G[i - 1][j].second - t);      
      }
    } else {
      for (int j = 0; j < G[i].size(); j++) {
        dp[pii(i, G[i][j].first)] = dp[pii(i + 1, G[i][j].second)];
      }
      if (i == 1) continue;
      ll mind = 1LL << 60;
      int up = 0, dw = G[i].size() - 1;
      for (int j = 0; j < G[i - 1].size(); j++) {
        while (up < G[i].size() - 1 && G[i][up].first <= G[i - 1][j].second) {
          mind = min(mind, dp[pii(i, G[i][up].first)] + G[i][up].first - G[i - 1][j].second);
          up++;
        }
        dp[pii(i, G[i - 1][j].second)] = min(dp[pii(i, G[i - 1][j].second)], mind);
      }
      mind = 1LL << 60;
      for (int j = G[i - 1].size() - 1; j >= 0; j--) {
        while (dw >= 0 && G[i][dw].first >= G[i - 1][j].second) {
          mind = min(mind, dp[pii(i, G[i][dw].first)] + G[i - 1][j].second - G[i][dw].first);
          dw--;
        }
        dp[pii(i, G[i - 1][j].second)] = min(dp[pii(i, G[i - 1][j].second)], mind);
      }
    }
  }

  ll ans = 1LL << 60;
  for (int i = 0; i < G[1].size(); i++) {
    ans = min(ans, dp[pii(1, G[1][i].first)] + abs(G[1][i].first - s));
  }
  cout << (ans == 1LL << 60 ? -1 : ans) << endl;

  return 0;
}