import sys
input = sys.stdin.readline

N, V, L = map(int, input().split())
dp = [[10**18]*(V+1) for _ in range(N+1)]
dp[0][V] = 0
prev_x = 0

for i in range(N):
    x, v, w = map(int, input().split())
    use = x-prev_x
    
    for j in range(V+1):
        if j<use:
            continue
        
        dp[i+1][j-use] = min(dp[i+1][j-use], dp[i][j])
        k = min(V, j-use+v)
        dp[i+1][k] = min(dp[i+1][k], dp[i][j]+w)

    prev_x = x

ans = 10**18
use = L-prev_x

for i in range(V+1):
    if i<use:
        continue
    
    ans = min(ans, dp[N][i])

if ans==10**18:
    print(-1)
else:
    print(ans)