fn run<'a, I, W>(mut scanner: I, mut writer: W)
where
    I: Iterator<Item = &'a str>,
    W: std::io::Write,
{
    macro_rules! scan {
        ([$t:tt; $n:expr]) => ((0..$n).map(|_| scan!($t)).collect::<Vec<_>>());
        (($($t:tt),*)) => (($(scan!($t)),*));
        (Usize1) => (scan!(usize) - 1);
        (Bytes) => (scan!(String).into_bytes());
        ($t:ty) => (scanner.next().unwrap().parse::<$t>().unwrap());
    }
    macro_rules! input {
        ($($($v:ident)* : $t:tt),* $(,)?) => ($(let $($v)* = scan!($t);)*);
    }
    
    input! {
        n: usize, q: usize,
        s: Bytes,
    }

    let mut sum = vec![vec![0; n + 1]; 26];
    for (i, s) in s.into_iter().enumerate() {
        sum[(s - b'a') as usize][i + 1] += 1;
    }
    for sum in sum.iter_mut() {
        for i in 0..n {
            sum[i + 1] += sum[i];
        }
    }

    for _ in 0..q {
        input! {
            l: Usize1, r: usize, mut x: usize,
        }

        for (i, sum) in sum.iter().enumerate() {
            let sum = sum[r] - sum[l];
            if sum < x {
                x -= sum;
            } else {
                writer.write_all(&[b'a' + i as u8]).ok();
                writer.write_all(b"\n").ok();
                break;
            }
        }
    }
}

fn main() {
    let ref mut buf = Vec::new();
    std::io::Read::read_to_end(&mut std::io::stdin(), buf).ok();
    let scanner = unsafe {
        std::str::from_utf8_unchecked(buf).split_ascii_whitespace()
    };

    let stdout = std::io::stdout();
    let writer = std::io::BufWriter::new(stdout.lock());

    run(scanner, writer);
}