use std::cmp::*;
// https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
macro_rules! input {
    ($($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)*}
    };
}

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, 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"));
}

const INF: i64 = 1 << 55;

fn squmul(a: &[Vec<i64>], b: &[Vec<i64>]) -> Vec<Vec<i64>> {
    let n = a.len();
    let mut ret = vec![vec![-INF; n]; n];
    for i in 0..n {
        for j in 0..n {
            for k in 0..n {
                ret[i][k] = max(ret[i][k], a[i][j] + b[j][k]);
            }
        }
    }
    ret
}

fn squpow(a: &[Vec<i64>], mut e: i64) -> Vec<Vec<i64>> {
    let n = a.len();
    let mut sum = vec![vec![-INF; n]; n];
    for i in 0..n { sum[i][i] = 0; }
    let mut cur = a.to_vec();
    while e > 0 {
        if e % 2 == 1 {
            sum = squmul(&sum, &cur);
        }
        cur = squmul(&cur, &cur);
        e /= 2;
    }
    sum
}

fn main() {
    input! {
        c: [usize1; 26],
        k: [i64; 26],
        n: usize,
        sabe: [(chars, usize1, usize1, i64); n],
    }
    let mut g = vec![vec![vec![-INF; 32]; 32]; 26];
    for (s, a, b, e) in sabe {
        for &c in &s {
            let idx = (c as u8 - b'A') as usize;
            g[idx][a][b] = max(g[idx][a][b], e);
            g[idx][b][a] = max(g[idx][b][a], e);
        }
    }
    let mut ans = vec![vec![]; 26];
    for i in 0..26 {
        for j in 0..16 {
            g[i][j + 16][j] = 0;
            g[i][j + 16][j + 16] = 0;
        }
        let pw = squpow(&g[i], k[i] + 1);
        ans[i] = pw[c[i] + 16].clone();
    }
    let mut ma = -INF;
    for i in 0..16 {
        let mut tot = 0;
        for j in 0..26 {
            tot += ans[j][i];
        }
        ma = max(ma, tot);
    }
    if ma > -INF / 2 {
        println!("{}", ma);
    } else {
        println!("Impossible");
    }
}