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

const INF: usize = 1usize << 60;


fn dijkstra(start: usize, paths: &Vec<Vec<(usize, usize)>>) -> Vec<usize> {
    let n = paths.len();
    let mut ret = vec![INF; n];
    let mut que = BinaryHeap::new();
    que.push((Reverse(0), start));
    ret[start] = 0;
    while let Some((Reverse(cost), u)) = que.pop() {
        if cost > ret[u] { continue; }
        for &(v, w) in paths[u].iter() {
            if ret[v] > ret[u] + w {
                ret[v] = ret[u] + w;
                que.push((Reverse(w), v));
            }
        }
    }
    ret
}

fn main() {
    let mut nml = String::new();
    std::io::stdin().read_line(&mut nml).ok();
    let nml: Vec<usize> = nml.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let n = nml[0];
    let m = nml[1];
    let l = nml[2]-1;
    let mut t = String::new();
    std::io::stdin().read_line(&mut t).ok();
    let t: Vec<usize> = t.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let mut paths = vec![vec![]; n];
    for _ in 0..m {
        let mut abc = String::new();
        std::io::stdin().read_line(&mut abc).ok();
        let abc: Vec<usize> = abc.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
        let a = abc[0]-1;
        let b = abc[1]-1;
        let c = abc[2];
        paths[a].push((b, c));
        paths[b].push((a, c));
    }

    if t.iter().filter(|&&v| v > 0).count() == 1 {
        println!("0");
        return;
    }
    let mut mapping = Vec::with_capacity(n);
    for i in 0..n {
        mapping.push(dijkstra(i, &paths));
    }
    let mut result = INF;
    for collect_point in 0..n {
        let collecting = (0..n).map(|i| t[i] * mapping[collect_point][i] * 2).sum::<usize>();
        let to_start = mapping[collect_point][l];
        let shortcut = (0..n).filter(|&first_pick| t[first_pick] > 0).map(|first_pick| {
                mapping[collect_point][l] + mapping[collect_point][first_pick] * 2 - mapping[l][first_pick] - mapping[first_pick][collect_point]
            })
            .max()
            .unwrap();
        result = result.min(collecting + to_start - shortcut);
    }
    println!("{}", result);
}