import algorithm, deques, heapqueue, math, sets, sequtils, strutils, sugar, tables

proc input*(): string =
    return stdin.readLine
proc chmax*[T: SomeNumber](num0: var T, num1: T) =
    num0 = max(num0, num1)
proc chmin*[T: SomeNumber](num0: var T, num1: T) =
    num0 = min(num0, num1)
proc `%=`*[T: SomeInteger](num0: var T, num1: T) =
    num0 = num0 mod num1

var
    xvw: seq[(int, int, int)]
    dp: array[2010, array[2010, int]]

proc solve() =
    var N, V, L, x, v, w: int
    (N, V, L) = input().split.map(parseInt)
    xvw = @[(0, 0, 0)]
    for _ in 0..<N:
        (x, v, w) = input().split.map(parseInt)
        xvw.add((x, v, w))
    xvw.add((L, 0, 0))

    const INF = 10^18
    for i in 0..N + 1:
        dp[i].fill(INF)
    dp[0][V] = 0

    var nv: int
    for i in 0..N:
        for j in 0..V:
            if xvw[i + 1][0] - xvw[i][0] <= j:
                dp[i + 1][j - (xvw[i + 1][0] - xvw[i][0])].chmin(dp[i][j])
            nv = min(V, j + xvw[i][1])
            if xvw[i + 1][0] - xvw[i][0] <= nv:
                dp[i + 1][nv - (xvw[i + 1][0] - xvw[i][0])].chmin(dp[i][j] + xvw[i][2])

    var ans = min(dp[N + 1])
    echo if ans != INF: ans else: -1

when is_main_module:
    solve()