import sys
def input():
	return sys.stdin.readline()[:-1]

n, v, l = map(int, input().split())
dp = [[10**15 for _ in range(v+1)] for _ in range(n+1)]
gas = [[0, 0, 10**15]] + [list(map(int, input().split())) for _ in range(n)]
dp[0][v] = 0
for i in range(1, n+1):
	for j in range(v - gas[i][0] + gas[i-1][0] + 1):
		dp[i][j] = dp[i-1][j + gas[i][0] - gas[i-1][0]]
	for j in range(v, -1, -1):
		dp[i][min(v, j + gas[i][1])] = min(dp[i][min(v, j + gas[i][1])], dp[i][j] + gas[i][2])

ans = 10**15
for j in range(v, l - gas[n][0] - 1, -1):
	ans = min(ans, dp[n][j])
if ans > 10**14:
	print(-1)
else:
	print(ans)