use std::io::{stdout, BufReader, BufWriter, Read, Write};

#[allow(unused_macros)]
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 = Read::bytes(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)*}
    };
}
#[allow(unused_macros)]
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)*}
    };
}
#[allow(unused_macros)]
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, bytes) => {
        read_value!($next, String).into_bytes()
    };
    ($next:expr, usize1) => {
        read_value!($next, usize) - 1
    };
    ($next:expr, $t:ty) => {
        $next().parse::<$t>().expect("Parse error")
    };
}

fn main() {
    let out = stdout();
    let mut writer = BufWriter::new(out.lock());
    solve(&mut writer);
    writer.flush().unwrap();
}

fn solve<W: Write>(mut writer: W) {
    #[allow(unused_macros)]
    macro_rules! print {
        ($fmt:expr) => {
            write!(writer, $fmt).unwrap()
        };
        ($fmt:expr, $($arg:tt)*) => {
            write!(writer, $fmt, $($arg)*).unwrap()
        };
    }
    #[allow(unused_macros)]
    macro_rules! println {
        ($fmt:expr) => {
            writeln!(writer, $fmt).unwrap()
        };
        ($fmt:expr, $($arg:tt)*) => {
            writeln!(writer, $fmt, $($arg)*).unwrap()
        };
    }

    // Main Code
    input! {
        n: usize,
        a: usize,
        x: [usize; n]
    }
    let M = 1000000007;
    let size = 100 * n + 1;
    let mut dp = vec![vec![0 as usize; size]; n + 1];
    dp[0][0] = 1;
    for i in 0..n {
        let mut newdp = vec![vec![0; size]; n + 1];
        for j in 0..=n {
            for k in 0..size {
                if j > 0 && k >= x[i] {
                    newdp[j][k] = dp[j][k] + dp[j - 1][k - x[i]];
                }
                else {
                    newdp[j][k] = dp[j][k];
                }
                newdp[j][k] %= M;
            }
        }
        dp = newdp;
    }
    let mut ans = 0 as usize;
    for i in 1..=n {
        if i * a >= size {
            break;
        }
        for b in i * a .. size {
            ans += dp[i][b];
            ans %= M;
        }
    }
    println!("{}", ans);
}