import java.io.*; import java.util.*; import java.util.stream.*; public class Main { public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int n = sc.nextInt(); int m = sc.nextInt(); int k = sc.nextInt(); int s = sc.nextInt(); int t = sc.nextInt(); ArrayList> floors = new ArrayList<>(); for (int i = 0; i < n; i++) { floors.add(new TreeMap<>()); } int[] buils = new int[m]; int[] lefts = new int[m]; int[] rights = new int[m]; for (int i = 0; i < m; i++) { buils[i] = sc.nextInt() - 1; lefts[i] = sc.nextInt(); rights[i] = sc.nextInt(); floors.get(buils[i]).put(lefts[i], null); floors.get(buils[i] + 1).put(rights[i], null); } floors.get(0).put(s, null); floors.get(n - 1).put(t, null); int idx = 0; for (TreeMap map : floors) { for (int x : map.keySet()) { map.put(x, idx++); } } ArrayList> graph = new ArrayList<>(); for (int i = 0; i < idx; i++) { graph.add(new ArrayList<>()); } for (TreeMap map : floors) { int prev = -1; for (int x : map.keySet()) { if (prev != -1) { int diff = x - prev; graph.get(map.get(prev)).add(new Path(map.get(x), diff)); graph.get(map.get(x)).add(new Path(map.get(prev), diff)); } prev = x; } } for (int i = 0; i < m; i++) { graph.get(floors.get(buils[i]).get(lefts[i])).add(new Path(floors.get(buils[i] + 1).get(rights[i]), 0)); graph.get(floors.get(buils[i] + 1).get(rights[i])).add(new Path(floors.get(buils[i]).get(lefts[i]), 0)); } int start = floors.get(0).get(s); int goal = floors.get(n - 1).get(t); PriorityQueue queue = new PriorityQueue<>(); queue.add(new Path(start, 0)); long[] costs = new long[idx]; Arrays.fill(costs, Long.MAX_VALUE); while (queue.size() > 0) { Path p = queue.poll(); if (costs[p.idx] <= p.value) { continue; } costs[p.idx] = p.value; for (Path x : graph.get(p.idx)) { queue.add(new Path(x.idx, x.value + p.value)); } } if (costs[goal] == Long.MAX_VALUE) { System.out.println(-1); } else { System.out.println(costs[goal]); } } static class Path implements Comparable { int idx; long value; public Path(int idx, long value) { this.idx = idx; this.value = value; } public int compareTo(Path another) { if (value == another.value) { return 0; } else if (value < another.value) { return -1; } else { return 1; } } } } class Utilities { static String arrayToLineString(Object[] arr) { return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n")); } static String arrayToLineString(int[] arr) { return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new)); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public int[] nextIntArray() throws Exception { return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }