import sys

sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


N,V,L = MI()
XVW = [(0,0,0)]+[tuple(MI()) for _ in range(N)]
XVW.sort()

inf = 10**18
dp = [[inf]*(V+1) for _ in range(N+1)]
# dp[i][j] = i番目の地点に到達した際に、j以上の燃料を残すために必要な費用の最小値

for j in range(V+1):
    dp[0][j] = 0

for i in range(1,N+1):
    x,v,w = XVW[i]
    d = x-XVW[i-1][0]
    for j in range(V+1):
        if j+d <= V:
            dp[i][j] = min(dp[i][j],dp[i-1][j+d])
        if max(j-v,0)+d <= V:
            dp[i][j] = min(dp[i][j],dp[i-1][max(j-v,0)+d]+w)

y = L-XVW[-1][0]

if y > V:
    print(-1)
else:
    ans = dp[-1][y]
    if ans >= inf:
        print(-1)
    else:
        print(ans)