use std::cmp::*;
use std::io::*;
const INF: usize = 40;

fn main() {
    let mut s: String = String::new();
    std::io::stdin().read_to_string(&mut s).ok();
    let mut itr = s.trim().split_whitespace();
    let n: usize = itr.next().unwrap().parse().unwrap();
    let v: usize = itr.next().unwrap().parse().unwrap();
    let l: usize = itr.next().unwrap().parse().unwrap();
    let mut a = Vec::new();
    a.push((0, 0, 0));
    for _ in 0..n {
        a.push((
            itr.next().unwrap().parse().unwrap(),
            itr.next().unwrap().parse().unwrap(),
            itr.next().unwrap().parse().unwrap(),
        ));
    }
    a.push((l, 0, 0));

    let mut dp: Vec<Vec<usize>> = vec![vec![INF; 11]; 11];
    dp[0][v] = 0;

    for i in 0..n + 1 {
        for j in 0..v + 1 {
            let k = min(j + a[i].1, v);
            let diff = a[i + 1].0 - a[i].0;
            if k >= diff {
                dp[i + 1][k - diff] = min(dp[i + 1][k - diff], dp[i][j] + a[i].2);
            }
            if j >= diff {
                dp[i + 1][j - diff] = min(dp[i + 1][j - diff], dp[i][j]);
            }
        }
    }
    let mut ans = INF;
    for i in 0..v + 1 {
        if dp[n + 1][i] != INF {
            ans = min(ans, dp[n + 1][i]);
        }
    }
    if ans == INF {
        println!("-1",)
    } else {
        println!("{}", ans);
    }
}