local mmi, mma = math.min, math.max
local n, v, l = io.read("*n", "*n", "*n")
local dp = {}
for i = 1, v + 1 do
  dp[i] = false
end
dp[v + 1] = 0
local pos = 0
for i = 1, n do
  local x, z, w = io.read("*n", "*n", "*n")
  -- walk
  local len = x - pos
  for j = len + 1, v + 1 do
    dp[j - len] = dp[j]
  end
  for j = v + 1 - len + 1, v + 1 do
    dp[j] = false
  end
  -- add
  for j = v, 1, -1 do
    if dp[j] then
      local dst = mmi(v + 1, j + z)
      if not dp[dst] then
        dp[dst] = dp[j] + w
      else
        dp[dst] = mmi(dp[dst], dp[j] + w)
      end
    end
  end
  pos = x
end
do
  local len = l - pos
  for j = len + 1, v + 1 do
    dp[j - len] = dp[j]
  end
  for j = v + 1 - len + 1, v + 1 do
    dp[j] = false
  end
end
local ret = false
for i = 1, v + 1 do
  if dp[i] then
    if not ret then
      ret = dp[i]
    else
      ret = mmi(ret, dp[i])
    end
  end
end
print(ret or -1)