import sys
readline = sys.stdin.readline
MAX = int(1e18)

N, M, K, S, T = map(int, readline().split())
R = [[] for _ in range(N)]
R[0].append([0, S, 0])
for _ in range(M):
	a, b, c = map(int, readline().split())
	R[a].append([b, c, MAX])

for i in range(1, N):
	R[i].sort()
	k_max = len(R[i - 1]) - 1
	k = 0
	min_val = MAX
	for j in range(len(R[i])):
		while k <= k_max and R[i - 1][k][1] <= R[i][j][0]:
			min_val = min(min_val, R[i - 1][k][2] - R[i - 1][k][1])
			k += 1
		R[i][j][2] = min(R[i][j][2], min_val + R[i][j][0])
	k = k_max
	min_val = MAX
	for j in range(len(R[i]) - 1, -1, -1):
		while k >= 0 and R[i - 1][k][1] >= R[i][j][0]:
			min_val = min(min_val, R[i - 1][k][2] + R[i - 1][k][1])
			k -= 1
		R[i][j][2] = min(R[i][j][2], min_val - R[i][j][0])
	R[i].sort(key=lambda x:x[1])

ans = MAX
for r in R[N - 1]:
	ans = min(ans, abs(r[1] - T) + r[2])
print(ans if ans < MAX else -1)