N, V, L = map(int, input().split())
x = []
for i in range(N):
    t, m, p = map(int, input().split())
    if m == 0:
        continue 
    x.append([t, m, p])

dp = [[float('inf') for i in range(V + 1)] for j in range(L + 1)]
dp[0][V] = 0

for i in range(L):
    for j in range(1, V + 1):
        if dp[i][j] != float('inf'):
            for k in range(len(x)):
                if x[k][0] == i + 1:
                    dp[i + 1][min(j - 1 + x[k][1], V)] = min(dp[i + 1][min(j - 1 + x[k][1], V)], dp[i][j] + x[k][2])
            dp[i + 1][j - 1] = dp[i][j]

ans = float('inf')
for i in dp[L]:
    ans = min(ans, i)

print(ans if ans != float('inf') else -1)