macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        let mut next = || { iter.next().unwrap() };
        input_inner!{next, $($r)*}
    };
    ($($r:tt)*) => {
        let stdin = std::io::stdin();
        let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock()));
        let mut next = move || -> String {
            bytes
                .by_ref()
                .map(|r| r.unwrap() as char)
                .skip_while(|c| c.is_whitespace())
                .take_while(|c| !c.is_whitespace())
                .collect()
        };
        input_inner!{next, $($r)*}
    };
}

macro_rules! input_inner {
    ($next:expr) => {};
    ($next:expr, ) => {};

    ($next:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };

    ($next:expr, mut $var:ident : $t:tt $($r:tt)*) => {
        let mut $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };
}

macro_rules! read_value {
    ($next:expr, ( $($t:tt),* )) => {
        ( $(read_value!($next, $t)),* )
    };

    ($next:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
    };

    ($next:expr, [ $t:tt ]) => {
        {
            let len = read_value!($next, usize);
            (0..len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
        }
    };

    ($next:expr, chars) => {
        read_value!($next, String).chars().collect::<Vec<char>>()
    };

    ($next:expr, usize1) => {
        read_value!($next, usize) - 1
    };

    ($next:expr, $t:ty) => {
        $next().parse::<$t>().expect("Parse error")
    };
}

#[allow(unused_imports)]
use std::cmp::{min, max};
use std::collections::HashMap;

fn main() {
    input!{
        n: usize,
        h: usize,
        w: usize,
        mut rca: [(usize1, usize1, usize); n]
    }
    let mut ans = 0;
    let mut uf = UnionFind::new();
    for i in 0..h {
        uf.add_point((i, 0));
    }
    for i in 0..w {
        uf.add_point((i, 1));
    }
    rca.sort_by(|x, y| y.2.cmp(&x.2));
    for &(r, c, a) in &rca {
        if uf.size(&(r, 0)) == uf.esize(&(r, 0)) && uf.size(&(c, 1)) == uf.esize(&(c, 1)) {
            continue;
        }
        ans += a;
        uf.union((r, 0), (c, 1));
    }
    println!("{}", ans);
}

struct UFNode {
    parent: usize,
    rank: usize,
    size: usize,
    esize: usize
}

struct UnionFind<T> where T: std::cmp::Eq + std::hash::Hash {
    map: HashMap<T,usize>,
    nodes: Vec<UFNode>,
    next: usize,
    n_unions: usize
}

impl<T: std::cmp::Eq + std::hash::Hash> UnionFind<T> {
    fn new() -> UnionFind<T> {
        UnionFind{map: HashMap::new(), nodes: Vec::new(), next: 0, n_unions: 0}
    }

    fn add_point(&mut self, x: T) -> usize {
        let id = self.next;
        self.map.insert(x,id);
        self.nodes.push(UFNode{parent: id, rank: 0, size: 1, esize: 0});
        self.next += 1;
        self.n_unions += 1;
        id
    }

    fn get_id(&self, x: &T) -> Option<usize> {
        self.map.get(x).map(|x| *x)
    }

    fn find(&mut self, id: usize) -> usize {
        let p = self.nodes[id].parent;
        if p == id {
            return id;
        }
        let pr = self.find(p);
        self.nodes[id].parent = pr;
        pr
    }

    fn union(&mut self, x: T, y: T) {
        let idx = self.get_id(&x).unwrap_or_else(|| self.add_point(x));
        let idy = self.get_id(&y).unwrap_or_else(|| self.add_point(y));
        let xp = self.find(idx);
        let yp = self.find(idy);
        if xp == yp {
            self.nodes[xp].esize += 1;
            return;
        }
        let rx = self.nodes[xp].rank;
        let ry = self.nodes[yp].rank;
        if rx < ry {
            self.nodes[xp].parent = yp;
        } else if rx > ry {
            self.nodes[yp].parent = xp;
        } else {
            self.nodes[yp].parent = xp;
            self.nodes[xp].rank += 1;
        }
        let size = self.nodes[xp].size + self.nodes[yp].size;
        let esize = self.nodes[xp].esize + self.nodes[yp].esize + 1;
        self.nodes[xp].size = size;
        self.nodes[xp].esize = esize;
        self.nodes[yp].size = size;
        self.nodes[yp].esize = esize;
        self.n_unions -= 1;
    }

    fn size(&mut self, x: &T) -> usize {
        let id = self.get_id(x).unwrap();
        let idp = self.find(id);
        self.nodes[idp].size
    }

    fn esize(&mut self, x: &T) -> usize {
        let id = self.get_id(x).unwrap();
        let idp = self.find(id);
        self.nodes[idp].esize
    }
}


Measured memory_bytes: 25308