use std::{cmp::Reverse, collections::BinaryHeap};

use proconio::input;

fn main() {
    input! {
        n: usize, k: usize, x: i64,
        a: [i64; n],
    }

    let mut ans = i64::MIN;
    let mut sum = 0;
    let mut heap = BinaryHeap::new();
    for &a in &a {
        let b = a - x;
        sum += b;
        heap.push(Reverse(a));
        if heap.len() > k {
            sum -= heap.pop().unwrap().0;
        }
        ans = ans.max(sum);
    }
    println!("{ans}");
}