import numpy as np

N, V, L = map(int, input().split())
INF = 10 ** 18
dp = np.full(V + 1, INF)
dp[V] = 0
cur = 0
for _ in range(N):
    new_dp = np.full(V + 1, INF)
    x, v, w = map(int, input().split())
    if v == 0:
        continue
    dist = x - cur
    if dist > V:
        print(-1)
        exit()
    new_dp[:V + 1 - dist] = dp[dist:]
    dp = new_dp.copy()

    if v <= V:
        new_dp[v:] = np.minimum(new_dp[v:], dp[:-v] + w)
        new_dp[V] = min(new_dp[V], np.min(dp[-v:]) + w)
    else:
        new_dp[V] = min(new_dp[V], np.min(dp) + w)

    dp = new_dp.copy()
    cur = x

if L - cur > V:
    print(-1)
    exit()
ans = np.min(dp[L - cur:])
print(ans if ans != INF else -1)